The Diana model 10/Beeman 900 target pistol: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

Beeman 900
The Beeman 900 pistol is another form of Diana’s model 10.

Part 1
Part 2

History of airguns

This report covers:

  • Godfather’s Gold Gun Giveaway
  • Shooting the Beeman 900/Diana model 10
  • The test
  • RWS R10 Match Pistol pellets
  • Qiang Yuan Training pellets
  • Gamo Match pellets
  • JSB Match Heavy Weight
  • H&N Match Green
  • Discussion
  • Summary

Godfather’s Gold Gun Giveaway

I am selecting the winner of the Godfather’s Gold Gun Giveaway this weekend. After my selection I will contact the winner to see if the airgun is legal in his locale. I hope to announce a winner on Monday.

Shooting the Beeman 900/Diana model 10

This is a day I have long awaited. I have shot these pistols in the past, but never under my strict test conditions, so today I hope to start the “book” on this one!

The test

I shot the pistol rested at 10 meters. The pistol was rested on the sandbag, touching the bag just ahead of the triggerguard. That is okay because the Beeman 900 is recoilless.

I shot 5-shot groups because target airguns often make groups so small that shooting more than 5 is just a waste of pellets. I wore my 1.25-diopter reading glasses that make the front sight sharp and clear, which I always do with an open-sighted pistol.

I had no idea where this pistol was sighted, but I shot for group size and wasn’t as concerned with where the pellets landed. I could always adjust the sights as I went.

RWS R10 Match Pistol pellets

First to be tested was the RWS R10 Match Pistol pellet. I suspected it might be the best pellet for this pistol, just because of how carefully they are made.

I checked the target after the first shot to make certain the pellet hit the paper. After that I never looked again. The first shot was low in the 8-ring. But when I saw the group I was disappointed. Five R10 pellets went into 0.92-inches at 10 meters. That’s what a sport pistol should do — not a target pistol!

Beeman 900 R10 group
The Beeman 900 put five R10 Match Pistol pellets into 0.92-inches at 10 meters. I expected to see all five in something like that three shot group in the center.

Since the R10s shot low but seemed well-centered, I adjusted the rear sight up 7 clicks.

Qiang Yuan Training pellets

The Chinese Qiang Yuan Training pellet that was next often surprises me with its accuracy. But not today. Five of them went into 0.865-inches at 10 meters. That’s not much better than the R10s.

Beeman 900 Qiang Yuan Training group
Five Qiang Yuan Training pellets went into 0.865-inches at 10 meters.

Obviously 7 clicks up was way too much adjustment, so after seeing this group I dialed the rear sight down three clicks.

Gamo Match pellets

Gamo Match pellets are certainly not world class, but I have seen them do some surprising things in the past. So I gave them a chance in this pistol. But they blew it!

I miscounted while shooting, so I shot 6 Gamo Match at this target and they went into a group measuring 1.253-inches between centers. Not much I can say about that.

Beeman 900 Gamo Match group
Six Gamo Match pellets went into a group measuring 1.253-inches between centers at 10 meters.

After seeing this group I dialed the rear sight another two clicks down.

JSB Match Heavy Weight

Next I fired 5 JSB Match Heavy Weight pellets. This time things were better, though not as good as I had hoped. Five pellets landed in a group measuring 0.789-inches between centers. This time the group is almost perfectly centered, so I planned to leave the sights alone from this point on.

Beeman 900 JSB Match Heavy group
Now we are getting somewhere! Five JSB Match Heavy Weight pellets grouped in 0.789-inches.

H&N Match Green

The last pellet I tested was the lead-free H&N Match Green. These did well in the velocity test and have been accurate before in other airguns. In the Beeman 900 five of them went into 0.888-inches at 10 meters. It’s too open to be exciting, though it’s not much larger than the JSB Match pellet group that is the best of the test.

Beeman 900 HN Match Green group
Five H&N Match Green pellets went into 0.888-inches at 10 meters.

Discussion

Today’s test was disappointing. What you see here is not what I expected. I expected far better. The trigger is spot-on and we know the pistol has all the power it’s supposed to. But try as I might I just could not get this pistol to shoot. I expected a gold dollar group today (under 0.15-inches) but we didn’t even come close to a trime (under 0.20-inches).

I do note that the heaviest pellet was also the most accurate. And my first Diana model 10 did well with the 8.2-grain RWS Meisterkugeln. So a second test with heavier target pellets is in the works. I won’t do it right away, to allow us to see some other historical airguns in the interim, but I will return to this pistol.

Summary

That’s it for today. Sometimes things don’t turn out the way you expect them to, but you just keep on trying.


The Diana model 50 underlever: Part 6

by Tom Gaylord
Writing as B.B. Pelletier

Diana 50
Diana model 50 underlever.

Part 1
Part 2
Part 3
Part 4
Part 5

A history of airguns

This report covers:

  • The test
  • Sight in
  • RWS Superdomes
  • The trigger
  • RWS Supermags
  • Feel of firing|
  • RWS Hobbys
  • Why shoot only RWS pellets?
  • H&N Baracuda 4.50 mm head
  • Discussion
  • Summary

Today I shoot the Diana model 50 underlever with sporting sights from 25 yards. Let’s see what she’ll do!

The test

I shot indoors from 25 yards off a sandbag rest. I used the artillery hold with the rifle rested on my off hand, about 8-9 inches forward of the triggerguard. The Diana 50 is an underlever, and that steel cocking mechanism makes it heavy up front, so this is the most comfortable way to stabilize it. I shot 10-shot groups at 10-meter pistol targets

Sight in

Because I moved the rear sight forward for this test, I had to sight in the rifle again. The first shot was from 12 feet and impacted at the top of my front sight, so I called it good and backed up to 25 yards. I knew the shots would hit higher from back there, but since the first shot hit at 6 o’clock on the bull and this was a pistol target, I reckoned there was plenty of room.

RWS Superdomes

The first pellet I tested was also the sight-in pellet — the RWS Superdome. At 10 meters this pellet did quite well, though it opened up when I shot it at 25 yards with the peep sight. My group of ten from Part 4 measured 1.044-inches between centers.

This time with the sporting sights 10 Superdomes went into 1.994-inches at the same 25 yards. Throw out the pellet that hit to the left of the rest and 9 are in 1.166-inches. So — not much different but not as good as with the peep sight. There were no pulled shots in this test.

Diana 50 Superdome
Ten RWS Superdomes made a 1.994-inch group at 25 yards, with 9 in 1.166-inches.

The trigger

I have to comment on the trigger. I never adjusted it like I said I might and I think I know why. It’s breaking as a single-stage trigger with a light pull. I can feel the trigger blade move, but with those ball bearings there is absolutely no creep (an erratic start and stop in the blade as it is pulled).

I think this trigger is what reader RidgeRunner talks about when he says he likes single-stage triggers. The Webley Senior straight grip pistol I traded to him has the same sort of trigger, only its blade moves a lot farther. This one is almost a target trigger. It’s just enough resistance to let the shooter know what he is doing.  I normally don’t like single-stage triggers, but I do like this one! I’m glad I left it the way it was.

RWS Supermags

The 9.3-grain RWS Supermag wadcutter is a pellet I haven’t tried in this rifle before. So I thought, “What the heck?”

Ten Supermags went into 1.61-inches at 25 yards. But the firing cycle became very loud and deep — much different than with the Superdomes. The shots also landed lower on the paper.

Diana 50 Supermag
Ten RWS Supermags went into 1.61-inches at 25 yards.

Feel of firing

As it is now set up this Diana 50 does not vibrate at the shot. However, the piston must be heavy, because there is a pronounced forward lurch on every shot.

RWS Hobbys

The next pellet I tried was the 7-grain RWS Hobby wadcutter. What a marked difference in the shot cycle they made! Hobbys shot very quiet and smooth. I hoped for a miracle in the accuracy department but alas, 10 pellets went into 1.732-inches at 25 yards.

Diana 50 Hobby
The Diana 50 put 10 RWS Hobby pellets into this 1.732-inch group at 25 yards.

Why shoot only RWS pellets?

I would normally run in some JSBs or pellets from some other manufacturer, so why have I shot three pellets from RWS? I did it because in my experience, Diana airguns — especially the vintage ones like this model 50 — really do well with RWS pellets. However, sometimes you have to step out of the ordinary and try something different.

H&N Baracuda 4.50 mm head

I thought I needed to do something drastic to turn things around. So the final group I shot was 10 H&N Baracudas with 4.50 mm heads. From what I saw with the 9.3-grain Supermags, these 10.65-grain domes are way too heavy for this powerplant, and when I shot the first one it was confirmed. The rifle made a loud sound that almost protested the use of this pellet. So, why did I do it?

I have done this with other vintage Dianas many times. Particularly the .22-caliber Diana 27 seems to love the heavy Baracuda against all odds. It makes no protest and tends to group quite well. But this model 50 is a different proposition altogether. But how did it group?

Ten Baracudas went into 1.451-inches at 25 yards. Five of them are in a very small cluster, but the other five are scattered. The group is nice and round, despite being on the large side. It is the smallest group of the test.

Diana 50 Baracuda
Ten H&N Baracuda domes with 4.50 mm heads went into 1.451-inches at 25 yards.

I think Baracudas have such thick skirts that they are not blowing out in the loading tap and sealing the bore as well as they could. Hobbys, in sharp contrast, seal the bore quite well.

Discussion

I was hoping this test would prove that the Diana 50 is a tackdriver, but I guess that is not to happen under my watch. She is a well-made springer that shows innovation in many places, but she’s not a natural shooter like some other Dianas I have had.

I may not have found the right pellet for this rifle — that’s a forgone conclusion. But I think I have given her a good test, nevertheless.

I will say that the little lube tune I gave the rifle in Part 5, while switching the rear sight, was the best thing I could have done besides leaving that trigger alone.

This underlever is solidly built, well finished and very smartly designed. Just looking at her and holding her makes me feel good.

Summary

That will be it for the Diana 50. I’m so glad to have had the opportunity to look this deeply into such a fine spring gun.


The Diana model 50 underlever: Part 5

by Tom Gaylord
Writing as B.B. Pelletier

Diana 50
Diana model 50 underlever.

Part 1
Part 2
Part 3
Part 4

A history of airguns

This report covers:

  • Move the rear sight
  • Rear sight move forward
  • Change the sight notch
  • Rear sight adjustability
  • Not finished
  • Some disassembly required
  • Three stock screws
  • Wait a minute!
  • Glue the stock
  • Dry mainspring
  • Assembly
  • Velocity check
  • JSB Exact RS
  • RWS Hobby
  • Cocking effort
  • Summary

To give you guys a break from the Crosman MAR177 today I started exploring the History of Airguns web page. Have you seen how the History of Airguns is laid out now? It’s now a simple timeline. Clicking on the dates brings up the past historical articles.

In checking to see whether they all made it to the timeline, I discovered this report from 2017, in which I mentioned wanting to shoot the rifle with an open rear sight. I never did that, so today is the day. I thought I’d just have to move the rear sight but you know how little projects sometimes expand? This one sure did! This will be the tale of what happened.

Move the rear sight

I told you in Part 2 that the rear sight can be transformed into a sporting sight by removing the peephole. There is also a forward ramp on the spring tube for the sporter sight, so there is enough distance for the eye to pick up the rear notch.

Diana 50 two ramps
The Diana 50 has two ramps for the rear sight. The one on the rear is for the target peep and the one in the front is for when the sight is converted into a sporting sight.

The tops of each ramp are serrated with grooves that match the special “foot” that’s on the bottom of the sight. This foot is pressed down into those grooves and makes a mechanical bond that will not slip from recoil.

Diana 50 rear sight peep off
After removing the rear sight from the rifle, I removed the peephole from the sight, transforming it into a sporting rear sight.

Diana 50 rear sight top
That lone screw on top of the rear sight pushes the foot down into the grooves in the ramp.

Diana 50 rear sight foot
The foot that contacts the grooves on the ramps can be seen underneath the rear sight.

Rear sight move forward

To use the rear sight as a sporting sight with a notch, I had to move it forward. I moved it to the front end of the forward sight base ramp. Then I screwed that lone screw back down and the foot meshed with the grooves in that ramp to secure it.

Diana 50 sporter
|With the rear sight moved forward the Diana 50 is transformed into a sporter.

Change the sight notch

One more thing needs to be done to complete the change to a sporter. I have dialed up the wide target post front sight element, and the rear notch has to correspond. It had been set on a wide cupped notch when the peep was installed, but the notch plate was rotated to put a square notch in its place. 

Diana 50 front sight
The Diana 50 has four different front sight elements that can be dialed into place. This is the target post.

To rotate the square notch plate, the rear sight needs a little elevation so the corners of the plate can clear the sight base on the rifle. That’s how low the rear sight adjusts!

Diana 50 notch plate
This rear sight notch plate has three notches — a square, a Vee and a U-shaped one. The fourth large U-shaped notch on the left is for visual clearance when the peep sight is clamped on.

Rear sight adjustability

I was surprised to see how much elevation adjustment there is in this particular rear sight. 

Diana 50 elevation adjustment
The rear sight adjusts up very far and the wheel that adjusts it has ten clicks for each step seen on the bottom plate of the sight assembly. The numbers on the top plate tell you which range of elevation the sight is in.

Not finished

Since it’s been so long since the last report, I read Part 4 thoroughly to see how the rifle was performing. I read that the rifle buzzed when it fired in the last test, which is to be expected with these older spring guns. But in this day and age we don’t have to put up with it, do we? I probably know what you are thinking. You think I stripped down the action and gave it a complete lube tune, but this time I didn’t. Instead I did almost exactly what I said I might do at the end of Part 4.

“There is a little bit of buzz when it fires, so it might be necessary to inject some Almagard 3752 grease into the mainspring to quiet down the powerplant. That could only make the shooting experience that much better. I might have a go at the trigger adjustment while the stock is off (for access to the mainspring). Don’t know if I will do any of this, but I’m writing it down as a reminder.”

I thought, “Why not?” The rifle is ready for another accuracy test, so why not do what I thought about last time? Only my tube of Tune in a Tube grease is so low that it no longer injects. I had purchased a 14-ounce grease gun tube of Almagard 3752 grease (same stuff as TIAT), but that can only be applied when the gun is apart and there is access to the parts to apply the grease directly. However, as I was rooting though my lubricant shelf my eye fell on the injector tube of Extreme Weapons Grease.

Diana 50 EWG
This tube of Extreme Weapons Grease is nearly full!

I used EWG on my Webley Hurricane we recently tested, and you may remember that it resolved all the problems I had with galling. It’s a thick grease like TIAT, so once more I decided to give it a try.

Some disassembly required

I didn’t want to completely disassemble the Diana 50’s powerplant, but to get to the mainspring I had to at least get the action out of the stock. And that project turned into the rest of my day!

Three stock screws

The action is held in the stock by three screws. The front triggerguard screw threads into the spring tube like we see on most spring guns. The threads are longer than I expected but there were no surprises.

The cross-bolt forearm screw is actually a proprietary two-piece affair, with a threaded bushing that holds the cross-bolt. It’s just as complex as the bolt itself. It came out easily, though the threads were about twice as long as I expected.

Diana 50 bolts
The front triggerguard screw is at the upper right. The stock cross-bolt and bushing are the two lower items. The bushing is actually half of the axel for the underlever during cocking.

With those two screws out I expected to separate the barreled action from the stock. Unfortunately there was one more screw, or nut, to deal with. Diana put a nut and washer on the threaded post that the underlever locks to. It has to come off and I saw the forearm had cracked from some force that could have been applied in the past.

Diana 50 forearm nut
The forearm is also held on by this nut that screws to the post where the underlever latches when closed. The stock has cracked along the grain — probably from someone trying the separate the stock from the barreled action before this nut was removed.

I looked at that nut and thought to myself, “Oh no! I have to make a special spanner to grab that nut!” I then spent the next 20 minutes looking though all my parts and tools to see what I could use to make the spanner. I could sacrifice a small socket from my tool kit and use a Dremel to grind away the sides until there were two short posts to fit into the notches on that nut. I looked and looked, but found nothing. If the socket was large enough to fit the notches it was too wide to fit into the tight channel in the stock. If it was small enough to fit in the channel it wasn’t wide enough to grab the two notches.

Then I thought about a flat piece of steel. That would be even easier to grind to shape, but the only piece I found was the flat tip of my longest screwdriver — the one I use to loosen the long screws in rifle butts that are held to their actions that way. I didn’t want to ruin it, because it took me years of combing though pawnshops to find it!

I decided that after lunch I would go to the hardware store and just buy a piece of steel of the right width. Then I stopped for lunch.

Wait a minute!

After lunch I decided to try one more thing before going to the store. I put the blade of a small screwdriver in one of the notches and tried to unscrew the nut. It was loose and came right off! I had wasted all that time thinking I had to make a special tool when the solution was so simple! Boy, am I glad I checked! The nut came off in less than a minute and the stock could be separated from the barreled action. I now saw that the washer under the nut is actually a spacer.

Diana 50 nut and washer
The nut and washer/spacer are off.

Glue the stock

Now that the stock was separated, I put some wood glue on both sides of the crack and troweled it in with the flat blade of a screwdriver. Then I clamped the stock to hold for several hours while I attended to other things. I left the repair clamped for about three hours and when the clamp was removed the crack was no longer visible.

Dry mainspring

With the action out of the stock and the cocking link removed I could see that the mainspring was bone-dry. No wonder the rifle buzzed a little when it fired!

Diana 50 mainspring
The mainspring was bone-dry. If ever there was any grease or oil on it, it’s now long gone.

Using the injector on the EWG tube I injected grease everywhere I could reach — including some on the body of the piston. I also lubed the cocking linkage with EWG, as it is under considerable stress when the rifle cocks. And I lubed both the bushing and the cross-bolt that the cocking link pivots on.

Diana 50 cocking link
The cocking link is in two parts and you can see the pivot hole that the stock cross-bolt fits through.

Assembly

After three hours the glue holding the crack in the stock had set, so I carefully assembled the rifle. When I shot it the first time after assembly, it was smooth. There was no hint of the vibration I formerly felt. As the rifle is fired the grease will slowly spread around the inside and hopefully get to all the parts.

Velocity check

Shooting the rifle was the proof of the job, but I wondered what the EWG had done to the velocity. This was an extremely thin application, so most of the velocity should still be there. I remembered that the Diana 50 was on the hot side for a target rifle, so I tested it with two of the pellets that had been used in the Part 2 velocity test.

JSB Exact RS

In Part 2 the JSB Exact RS pellet averaged 648 f.p.s. It now averages 690 f.p.s. The low was 667 f.p.s. and the high was 701 f.p.s. Only two shots were slower than 690 f.p.s. The only explanation I can offer for the increase is I lubricated the piston seal back in 2017. It must have soaked all through the leather piston seal by now.

In 2017 the RS pellet velocity varied by 136 f.p.s. In this test it varied 34 f.p.s. I think the piston seal is now working as it should.

RWS Hobby

In Part 2 the RWS Hobby pellet averaged 673 f.p.s. with a 45 f.p.s. spread. It now averages 680 f.p.s. with a 20 f.p.s. spread. 

Cocking effort

In Part 2 the rifle cocked with 25 lbs. of effort. It still cocks with that much force. It has been so long since I last shot the rifle that I can’t comment on any difference in the feel during cocking.

Summary

This has been a long-delayed Part 5 report on the Diana model 50 underlever. I still have accuracy to test with the sporting sights, so there is more to come. It’s great to be back with this old sweetie!


Crosman MAR 177: Part 6

by Tom Gaylord
Writing as B.B. Pelletier

Crosman MAR
The MAR177 from Crosman.

Part 1
Part 2
Part 3
Part 4
Part 5

History of airguns

This report covers:

  • Sight-in
  • First group
  • Qiang Yuan Olympic pellets
  • RWS Hobby
  • JSB Exact RS
  • Discussion
  • Summary

You asked me to back up to 25 yards with the Crosman MAR177 and today is the day I do it. It should prove to be an interesting report.

Sight-in

Because I was using the iron sights that came with the rifle, I skipped the sight-in at 12 feet and went straight to 25 yards. My sight-in pellet was the Air Arms Falcon that was so accurate in the test at 10 meters.

The first shot went two inches high at 25 yards. After seeing that I adjusted the rear sight down 5 clicks. I had adjusted it up the other day for photography when I was exploring its adjustability and writing Part 5.

Dropping 5 clicks dropped the second pellet 8 tenths of an inch, so I was still above the bullseye. I then adjusted the rear sight as low as it would go, which was only another 6 clicks. Then I just shot the remaining 8 pellets without looking through the spotting scope again.

I’m not going to measure this “group” because of the sight adjustments that were made. But I will let you see it.

MAR sight in
The sight-in target was shot from 25 yards with Falcon pellets. The 8 shots in the black were fired with the same sight setting.

Obviously this pellet is hitting too high, and the rear sight is as low as it will go. The only solution is to adjust the front sight higher. I used my new 1/8-inch roll pin punch to adjust the front post up 5 clicks. Remember, adjust the front sight in the direction opposite of how you want the pellet to move.

First group

I shot ten more Falcons after adjusting the front sight up. Ten pellets went into a group that measures 0.793-inches between centers. I pulled the second shot because I was trying to take up the stage one trigger pull and I fired the rifle before I was settled in for the shot. So I am blaming the trigger for that shot. However, even with that I got a decent group at 25 yards with iron sights. But the group is at the bottom of the bull. Apparently the front post adjustment moves the strike of the rounds farther than the rear sight adjustment.

Falcon group
The group of Falcons after adjusting the front post is 10 shots in 0.793-inches at 25 yards. Adjusting the front post up 5 clicks dropped the group to the bottom of the bull.

Qiang Yuan Olympic pellets

Next to be tested were the Qiang Yuan Olympic pellets. These weigh almost a full grain more than the Falcons, so I did not change the sight setting. I did not look at the target while shooting this group and it wasn’t until I walked down to the bullet trap to change the target that I saw what had happened. Ten pellets landed in a round group that measures 0.411-inches between centers. It’s the best group of the test, and I was astonished that the MAR could shoot this well. Five shots landing this tight might be called luck, but ten is something more. Ten shots this tight tell us that with the right pellet the MAR can shoot!

Chinese Olympic group
The MAR177 put ten Qiang Yuan Olympic pellets into 0.411-inches at 25 yards. This is the best group of the test.

After seeing how low on the bull the Chinese pellets hit I adjusted the rear sight up one more click up — making the total rear sight adjustment 6 clicks up.

RWS Hobby

The next pellet I tested was the RWS Hobby that did well at 10 meters. At 25 yards the MAR put 10 of them into a 1.098-inch group. Obviously Hobbys fell off at this distance, as we expect all wadcutters to. Can’t figure out the Qiang Yuan Olympic pellets though!

Hobby group
Then Hobby pellets went into 1.098-inches at 25 yards.

Obviously one click up did not move the shots high enough so I adjusted the rear sight another 2 clicks up. That’s a total of 8 clicks up after I adjusted the front post 5 clicks up.

JSB Exact RS

The last pellet I tested was the JSB Exact RS. This dome is similar to the Falcon pellet so I thought it might be a good one for the MAR. This time the rifle put 10 pellets into 0.923-inches at 25 yards. This group was a little higher in the bull but it was also a trifle off to the left.

RS group
The MAR shot 10 JSB Exact RS pellets into 0.923-inch group at 25 yards.

Discussion

The MAR177 shot better at 25 yards than I expected — at least for one pellet. The sights allow for precise shot placement because there are elevation adjustments front and rear.

I think I will call this test finished and move on to mount a scope on the MAR. That should give us a good look at the potential accuracy.

I still don’t care for the trigger. I think it was the reason for my thrown shot on the first group and I have to get accustomed to it every time I shoot the rifle.

Summary

The Crosman MAR177 is performing as it was designed to. It’s a top-flight pellet gun upper for the AR-15. It fits any AR-15 receiver that has standard-sized 0.154-inch pins, as opposed to the larger 0.171-inch Colt-style assembly pins.

It is unregulated, and handles air sparingly, getting up to 160 shots on a fill with 145 of them differing in velocity by just 24 f.p.s. The 10-shot rotary magazine works well, as long as the rifle is level when cocked. If the muzzle is elevated there can be a jam or a failure to feed.

Crosman built the MAR with the best of materials. They made it to shine, and shine it does. I am excited to shoot it with a scope, but I believe I’ll give you a break before I do.


Peep sights: Part 4

by Tom Gaylord
Writing as B.B. Pelletier

Part 1
Part 2
Part 3

This report covers:

  • First encounter
  • The front sight
  • HOWEVER!!!
  • Irony
  • The deal
  • Problems with the post sight
  • Other front sights
  • Contrarians
  • Dial-a-sight
  • The best front sight insert
  • The clear aperture front sight
  • Summary

Today we will look at the front sight that works with the peep sight. Remember, the whole purpose of the peep sight is to eliminate the rear sight from the equation. So the front sight is of extreme importance.

First encounter

The first peep sight I even looked through was on a Winchester model 52 target rifle in an NRA-run course that taught me how to shoot. While other boys my age (10) were interested in baseball and football,  I was only interested in shooting. So I listened to every word the instructors said and I tried to do what they told me, to the best of my ability.

Winchester 52 rear sight
The Marble target sight on the Winchester 52 seemed remarkable to a 10-year-old boy!

There were also Springfield 1922 M2 target rifles available in this course. I tried one once and found I could not shoot it as well as I could the Winchester. Its peep sight seemed more primitive (it really wasn’t) and the front sight was just a naked post, where the Winchester had a globe with inserts. I also felt the trigger was not as responsive and the entire rifle that weighed only around 9 pounds, seemed too light. In later years I owned a 1922 Springfield and found it to be extremely accurate, but at age ten I wasn’t as accustomed to target rifles, and the heavier Winchester seemed to be the better choice.

The front sight

I shot the sights that they had and never had a chance to compare front sights. The Winchester 52 I shot had a narrow post front sight that looked as wide as the bullseye at 50 feet. I think that post sights were all they had available in that course, because that was how they taught us to see the sight picture.

sight picture
The sight picture.

HOWEVER!!!

And this is where my schooling began! One instructor told us to just touch the bottom of the bull with the top of the front post, while another instructor told us if our eyes were really sharp we should leave the smallest sliver of light between the bottom of the bull and the top of the front post. Which one was right?


The two competing sight pictures we were told were correct.

Irony

The irony was, both were right! Two different sight pictures that were both correct. But which one was really right?

As it turned out, they were two different sight pictures, either one of which worked well, as long as the shooter applied it consistently. But the instructors didn’t say that. One said one thing and another said the other and I floundered with it for many, many years.

The deal

As penance for all my enabling I will now explain how both sight pictures can be correct. It turns out that the sight picture where the top of the front post touches the bottom of the bull is the easier of the two sight pictures for most shooters to achieve and it is the one that I believe should be taught to everyone. It is the sight picture you have always read in my writing.

But some people have better eyes! The problem with the first sight picture is it’s difficult to tell how MUCH of the front post is actually touching the bottom of the bull. Some will barely touch it while others will flatten the bottom of the bull just a bit. And even that isn’t bad, as long as it’s done consistently. But it’s hard to do consistently. And when you vary you get vertical stringing, or in matches where each bull is shot separately — a lower score. 

Worse still is when the shooter does it while sighting in before the match. Then they just shoot a lower score than they should have and it is extremely difficult to figure out why.

If you have really sharp eyes it may be possible for you to control how much of a sliver of light you leave between the front post and the bull. I have played with that sight picture off and on for the past 50 years and finally decided my eyes have never been good enough to sight that way.

Problems with the post sight

All of the discussion above is the reason why the post front sight is not preferred today. In fact it has been out of vogue for many decades.

front posts
Three front post inserts — the right one obviously from a different globe. They illustrate the range of post sizes that are available.

I favor a narrow front post that is no wider than the bull, if I can get it. But other shooters like the wider posts and like to center the bull on them.

Other front sights

Before we look at the front sight that is widely regarded as the best, there are other front sights to consider. A peep sight allows for any kind of front sight, including types that cannot be used with an open rear notch.

Zimmer front sight
A Zimmerstutzen front sight is a tiny bead on a super-fine post. The bead goes over the target where you want the bullet to strike. Zimmers shoot at 49-50 feet (15 meters), so this is a game where good vision is a plus!

sporting front sights
These sporting sights can also be used with a peep sight. They are sometimes used with bullseye targets, but usually only when a post or aperture is unavailable.

4 points
What the…? I have never understood why a front sight insert like this exists. Is it for shooting Klingon warbirds?

Lyman sight inserts
This card of inserts for the Lyman 17 globe front sight has some strange ones on the upper and lower right.

Contrarians

And then there are those contrarian shooters who prefer to have their inserts appear to be hanging, rather than standing in the front globe. This happens most often with the front aperture insert. Since the aperture is simply a circle that’s centered inside another circle, and since the goal is to put a third circle, the bullseye, inside that, it makes no difference whether the aperture is standing or hanging.

Dial-a-sight

Finally, there have been a great many rimfire rifles whose front sight has several possible inserts, all contained in a unit that’s part of the rifle. Mossberg was famous for it!

Mossberg 46M
The front sight on this Mossberg 46M (a) has any of four possible front sight inserts, all contained within the front sight base!

The best front sight insert

For target shooting there is one front insert that stands above all others.  It is an aperture, just like the peep sight in the rear, only this one cooperates with the round shape of a bullseye to define the target with more precision than any other insert.

front aperture
The front aperture is the most consistent insert in the game.

Aperture front sights came in vogue after World War II and have remained there ever since. They are nearly as intuitive as the peep sight itself for aligning a bullseye. Only one thing remained — to get rid of the thick solid ring around the hole so target shooters wouldn’t get confused and shoot at the wrong bull. Because if they do they either lose the shot, or, if two bullets land on the same bull, only the lower score counts.

The clear aperture front sight

When the clear or transparent aperture front sight inserts came out they displaced all other inserts, leveling the playing field in the target shooting game. A shooter using a post front insert has no chance against them and too many shooters have shot the wrong bull to ignore the value of a less obstructed view of the target.

clear aperture
The clear aperture. As you can see, the holes come in sizes to suit the shooter. This one is 3.3mm. When light enters from the front (target), the beveled cut becomes a black ring.

In competition conditions with proper lighting, the beveled hole in the clear insert becomes black, but it is much thinner than the circle of the older steel inserts. The thickness of the black ring is controlled to some extent by the angle of the beveled cut. And it encircles and centers the bullseye perfectly. I doubt there is any world-class competitor today who does not use clear inserts.

Summary

This series was a look at peep sights, with the focus on how they help those who shoot with iron sights. In Parts one through three we looked at the peeps themselves, and today we looked at the front sight they interact with.

The peep sight is one of the most misunderstood pieces of the shooting world. It is far more important than many believe and yet it is overlooked and avoided by those who think it is difficult to use.


Crosman MAR 177: Part 5

by Tom Gaylord
Writing as B.B. Pelletier

Crosman MAR
The MAR177 from Crosman.

Part 1
Part 2
Part 3
Part 4

History of airguns

This report covers:

  • The test
  • Sig Match Ballistic Alloy
  • What happened?
  • Second group with Sig Match Alloy
  • What to do?
  • Air Arms Falcon
  • The trigger
  • Do triggers affect accuracy?
  • Ten Sig Match Ballistic Alloy
  • RWS Hobby
  • Qiang Yuan Olympic
  • Discussion
  • The rear sight does adjust!
  • Summary

I finally managed to schedule for a minute past midnight, so that is back to normal. Today’s report is a follow-on from last Friday’s report. I am still testing the Crosman MAR177 target rifle’s accuracy with the sights that came with it. And I learned something big today. I hope it will help all of you with your shooting.

Actually, I learned two big things today. I had a stupident that I hope will help the rest of you.

The test

I said at the end of Part 4 that I wanted to test the MAR again, and perhaps with different pellets. That test happens today.

Once again I shot the rifle from a rest at 10 meters. The test was identical to what I did last Friday, and I started with the pellet that proved to be the best — the Sig Match Ballistic Alloy wadcutter.

Sig Match Ballistic Alloy

This rifle was already sighted in as much as I was going to (read what I think about adjusting M16/AR-15 sights in the Part 4 section titled “Sighting in the MAR”), so I just shot the first group. I was relaxed and ready to shoot. Last Friday the MAR put five of these pellets into 0.152-inches at 10 meters. This time five went into 0.492-inches. Disgraceful!

Sig Match Alloy target
Five Sig Match Ballistic Alloy target pellets made this 0.492-inch group at 10 meters. Previously all five pellets had gone into an area the size of the central hole in this group.

What happened?

Am I loosing it? Can I not hold a good group anymore? Am I too old to be shooting? I have to shoot another group to disprove all the unkind thoughts that are running through my mind right now.

Second group with Sig Match Alloy

I concentrated more on the second group. This time I put 5 in 0.339-inches which is better. Better, but not good. If this pellet can put 5 into 0.152-inches it ought to put 10 into 0.20 inches, or so. It shouldn’t just fall apart this way.

Sig Match Alloy target 2
The second target with Sig Match Ballistic Alloy pellets was better, but not that good. Five pellets are 0.339-inches apart, c-t-c.

What to do?

At this point it was looking like the fault rested with me. I decided to try a different pellet, one that worked well in the first MAR. The Air Arms Falcon pellet is a dome that did very well in 2012.

Air Arms Falcon

I shot 5 Falcons into 0.36-inches. While that is no better than the previous group, something remarkable happened during this group. Let’s look at the group first and then I want to talk to you.

Falcon target
Five Air Arms Falcon pellets went into 0.36-inches at 10 meters. Not a particularly great group, but something great happened while I was shooting it.

The trigger

Remember I said in Part 4 that I had to get used to the Geisselle trigger all over again each time I shot the MAR? That was the key! While I was shooting the first group of Falcon pellets I suddenly focused on the trigger and all my problems went away. The Geisselle trigger is what caused the open groups in the first three targets!

The trigger has a very heavy first stage that’s followed by a second stage that breaks with just 8 ounces more pressure. I said earlier that stage two feels crisp, but that was a mistake. Not only is it not crisp, the Geisselle trigger’s second stage is very creepy when compared to a good airgun trigger. For an AR trigger I suppose it’s okay, but I am shooting the MAR like it is a target rifle and the trigger is not helping me one bit. It is fooling me, which is why I have to reacquaint myself with the trigger every time I shoot the MAR.

I discovered that while shooting the third target of 5 Falcons, and I was so certain that I had found the answer that I shot ten Falcons at the next target. They grouped in 0.254-inches, c-t-c. That’s right, TEN pellets landed in a group that is 0.106-inches SMALLER than five of the same pellets shot just before! And that was all because I now knew how to shoot the Geisselle trigger!

Falcon target 2
Ten Falcon pellets went into 0.254-inches at 10 meters, once I used the Geisselle trigger correctly.

Do triggers affect accuracy?

I have always maintained that triggers do not affect accuracy. They only affect how easy it is to be accurate. Well, that is only partially true, and because of that it is entirely wrong. In Part 4 and now again in Part 5, I have twice been fooled by the trigger at the beginning of the test. Once I learned the trick I have been able to snap back and shoot better. This Geisselle trigger has been a harsh learning tool for old BB!

I always thought in terms of triggers with heavy pulls. Shooters complain about Mauser and Springfield military rifle 2-stage triggers that break at 5 and 6 pounds, and I have had no trouble shooting well with them. But this Geisselle trigger has a heavy first stage that conceals a light but very creepy stage two that has been foiling my attempts at accuracy. Now that I knew stage two is creepy I could deal with it, and I did! I treated it just as I would a creepy single-stage trigger.

Ten Sig Match Ballistic Alloy

Now that I knew the trigger I fired 10 Sig Match Ballistic Alloy pellets next. They did so well in Part 4. Well I must have pulled one of the shots because what I got was nine shots in 0.319-inches, with a lone shot opening the group to 0.509-inches — all at 10 meters. It was not a called pull, but I think you can agree that it was me and not the rifle.

Sig Match Alloy target 3
Nine Sig Match Ballistic Alloy pellets went into 0.319-inches at 10 meters, with the tenth shot opening the group to 0.509-inches.

RWS Hobby

Remember I said I wanted to try some pellets I hadn’t shot before? I have already tried Falcons, so RWS Hobbys were next. Ten of them went into 0.304-inches at 10 meters. That’s surprisingly good for what is considered a practice pellet.

Hobby target
Ten RWS Hobby pellets made this nice round 0.304-inch group at 10 meters.

Qiang Yuan Olympic

The last pellet I tested was the Qiang Yuan Olympic target pellet. They did second-best in the Part 4 test, with 5 going into 0.226-inches. In this test the MAR177 put 10 in 0.255-inches at the same 10 meters.

Chinese Olympic target
Ten Qiang Yuan Olympic pellets went into 0.255-inches — the second smallest group of this test!

Discussion

I learned a valuable lesson about triggers in this test. They can cause inaccuracy in a way I never anticipated. People have been telling me that for years and I always argued against it, but now I see that I was wrong. This Geisselle trigger faked me out with a heavy first stage that concealed a creepy stage two. I was firing before I was ready! And I am not done confessing my mistakes.

The rear sight does adjust!

A reader named Bruce contacted me through my website to tell me that I was mistaken about the rear sight not adjusting. I then argued with him in the comments on the blog. But he was adamant and contacted me a second time off the blog to get my attention. Well, he got it!

I examined the MAR177 rear sight and saw that it clearly does adjust for elevation. Why did I think it didn’t? Was it the manual?

Well, the manual does clearly state that the rear sight adjusts for elevation, but it also goes into a lot of detail about adjusting the front sight. I think I had a flashback to my Army days when I read that and started remembering the bad old days. I ignored the rear sight instructions in the manual and was back at Fort Lewis in 1968 again. Thank you, Bruce, for keeping after me on this. It really does make a huge difference. Now I can shoot from 25 yards as so many readers have asked, and use the open sights as well as a scope.

MAR rear sight
The MAR177 rear sight does, indeed, adjust for elevation. My thanks to reader Bruce, for calling my attention to this fact.

The bottom line is when I make a mistake like this I want it to be brought out. The purpose of this blog is to instruct, period. BB Pelletier is just the imperfect tool that’s used to do it.

Summary

I told you at the beginning of this report that today would be special. I hope it has been. The rear sight oversight is a mistake anyone can make. Now that we are aware of it, the record of the MAR is more complete.

It’s the trigger lesson that really upset me. Oh, I can still work with almost any trigger devised by man. I’m just surprised that it took me so long to figure this one out.

What’s up next? I think next I will back up to 25 yards and give you all what so many have asked for. Now that I can adjust the rear sight, it won’t be difficult to get on target at this distance.


Crosman MAR 177: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

Crosman MAR
The MAR177 from Crosman.

Part 1
Part 2

History of airguns

This report covers:

  • Baseline with Hobbys
  • Today’s test
  • What is the average?
  • Second page of numbers
  • What does “estimate 601” on page 2 mean?
  • But — what is the average velocity?
  • Photos
  • Pressure gauge and fill pressure
  • Big lesson
  • Balanced valve
  • How do I know the ending air pressure?
  • Air Arms Falcons
  • RWS R10 Match Pistol
  • H&N Finale Match Light
  • Loading problems
  • Loudness
  • Summary

Today I test the velocity of the MAR177 I’m reviewing, and I have a baseline from the 2012 test I did, with which to compare it. Some of you asked me what velocity to expect. Well, it is all in the 6-part review I did on the first MAR177. Look at Part 3 of that series for the velocity test. 

Baseline with Hobbys

In that 2012 test I got an average of 609 f.p.s. from RWS Hobbys and the velocity varied by 32 f.p.s. The low was 593 f.p.s. and the high was 625 f.p.s. I got a shot count of 124 shots on one fill.

Today’s test

Today I shot 160 Hobbys on a fill. The fill pressure ranged from a high of 3200 psi to a low of about 2200 psi — according to my accurate carbon fiber tank gauge. Those starting and ending pressures are well above the pressure range of the first gun (which was 2900 psi to 1600 psi).

In those 160 shots my highest velocity was shot number 106 that registered 604 f.p.s. My lowest velocity was shots number 156 that registered 571 f.p.s. That is a spread of 33 f.p.s. for 160 shots. However, I thought the rifle fell off the power curve on shot number 145, where the velocity was 578 f.p.s. If I take the first 140 shots, the low was 580 f.p.s and the high was 604 f.p.s. That is a spread of 24 f.p.s. I can live with that.

What is the average?

I didn’t tell you the average velocity for Hobby pellets, did I?  The reason I didn’t is because of the huge amount of data I collected. Let me show you.

50 shots
These are the velocities of the first 50 shots.

100 shots
Shots 51-100.

150 shots
Shots 101-150.

160 shots
Shots 151-160.

There is no way I am entering that data into WordPress, because when I edit, the software makes me highlight EACH NUMBER, click backspace/delete and then hold down the Shift key and click Return! For EACH NUMBER!!!

If you are reading this on a smartphone you had best learn how to scroll because I am going to refer to those numbers A LOT!

Second page of numbers

Let’s look at shots number 91 and 92 at the top right of the second page. Why is the velocity 492 f.p.s.? Because I double-loaded a pellet by mistake! So — yes, it is possible to load more than 1 pellet, and I disregarded that velocity for this test. The average for that column is the lower 8 shots.

What does “estimate 601” on page 2 mean?

By the time I had fired 70 shots I saw the velocity start to rise and, at the time, I thought this rifle was going to average in the 600s with Hobbys. So I wrote my estimate of what the third column velocity average would be before shooting the string and then I took a picture of that page — so you could see that I was just guessing. And I missed the average velocity by 5 f.p.s.

estimate
I estimated what the next string’s average velocity would be.

But — what is the average velocity?

I’m not going to enter all those numbers again and find the average. But, if I take the averages for each string of shots from number 1 to 140 and combine them to find the average for all of those averages, that number is 594 f.p.s. I’m calling that the average velocity at which this MAR177 shoots 140 RWS Hobby pellets — with a low of 580 to a high of 604 f.p.s. It’s very close to the true average, if not right on. At that average velocity Hobbys developed 5.49 foot-pounds of energy.

The first MAR I tested in 2012 averaged 609 f.p.s. with Hobbys over 124 shots on one fill and this one averages 594 f.p.s. over 140 shots on a fill. The first MAR177 varied velocity of Hobbys by 32 f.p.s. over its range, this one varies 24 f.p.s. over its range. The first gun was faster and this one gets more shots per fill and is more consistent. But the tests of both guns give you a good idea of how the MAR177 performs.

Photos

Normally there aren’t any photos on velocity day. This time I took 22 photos — 18 of the pressure gauge before and after every ten shots. I will now show you a few of those but I won’t overload you.

Pressure gauge and fill pressure

I’ve already said that the valve in this MAR177 uses higher pressure than the first one I tested. It also uses higher pressure than the manual recommends. The manual says that 2900 psi is the maximum fill pressure. I filled to 3200 psi this time to get both the top and bottom of the power curve. That was the pressure I saw on my carbon fiber tank gauge when the fill was complete. Look at what the onboard gauge said.

fill
The onboard gauge read this when my accurate tank gauge said 3,200 psi. The needle is close to 3400 psi.

first string
After the first 10 shots the gauge read this.

50 shots
After 50 shots the gauge read like this.

100 shots
After 100 shots the gauge read like this.

140 shots
After 140 shots the gauge read like this. I am calling this the end of the power curve. This is as low as I will let the onboard gauge get when shooting the MAR.

160 shots
After 160 shots on one fill, this is what the onboard gauge read. 

Big lesson

This gauge illustrates a really big lesson. Do not go by what the small onboard gauge on your PCP says, unless you have tested it and know it’s right. When I worked at AirForce I took all the complaint calls and after the Condor came out many of them were complaining that the Condor wasn’t giving them all the performance they paid for. How did they know? They pressurized their rifle to 3,000 psi on their tank’s gauge (AirForce rifles did not have gauges on them in those days) and the velocity was way too low. I told them to keep shooting the rifle until the velocity increased to over 1,200 f.p.s. with .22-caliber Crosman Premiers and then I told them how to determine how much pressure their rifle needed to get that speed. Some were happy with that, but others insisted that they weren’t getting what they paid for if the gun did not perform at 3,000 psi. I had no good answer for them.

Their rifles got 20 good shots with .22-caliber Premiers at over 1,200 f.p.s. and yet they thought they were getting shortchanged because the gun wasn’t doing it at 3,000 psi on their gauge. Did they think they would get MORE shots at that velocity with the higher pressure? No, they wouldn’t. Some even knew that because they had tested the rifle before calling in.

What they were saying, in effect, was their new C8 Corvette may be capable of going 194 m.p.h., according to a calibrated radar gun, but when they do, the speedometer in the car only reads 177 m.p.h. Well — which do you want, a 194 m.p.h. car with a speedo that’s not quite right and sells for under $60,000, or a 194 m.p.h. car whose precision speedometer also reads 194 m.p.h. , making the car retail for $74,000? Some guys can adapt and others can’t.

There — I got that off my chest. Until someone else says the same thing.

Balanced valve

What you are seeing with the MAR177 is the result of a balanced valve. Did Crosman set it up just for me? Not unless they have a Wayback machine or a crystal ball! I bought this New Old Stock air rifle off Ebay five years after Crosman stopped making them. This is what can be done with a PCP when: 

1. The engineer knows what he is doing, and 
2. The velocity is kept low.

How do I know the ending air pressure?

Okay, smart guys. Wanna tell BB how he knows that the ending air pressure (after 140 shots) is really 2,200 psi and not what it says on the gun’s gauge (just under 2100 psi)? This is a test and you will be graded. Do not look on anyone else’s paper.

Air Arms Falcons

I tested Air Arms Falcon pellets next. This time I pressurized the rifle to 2900 psi (using my carbon fiber tank gauge) and only shot a string of 10 for each pellet that follows. I’ll start with the Falcon.

Ten Falcon pellets averaged 611 f.p.s. The low was 590 and the high was 617, so a difference of 27 f.p.s. At the average velocity Falcons developed 6.08 foot-pounds of energy.

RWS R10 Match Pistol

Next to be tested were 10 RWS R10 Match Pistol pellets. They averaged 619 f.p.s. with a spread from 609 to 627 f.p.s. That’s a difference of 18 f.p.s. At the average velocity the R10 Match Pistol pellet develops 5.96 foot-pounds at the muzzle.

H&N Finale Match Light

The last pellet I tested was the H&N Finale Match Light. It was also the heaviest pellet. They averaged 592 f.p.s. with a spread that went from 586 to 598 f.p.s. — a difference of 12 f.p.s. At the average velocity this 7.87-grain pellet developed 6.13 foot-pounds at the muzzle.

Loading problems

While I was testing the last three pellets I encountered a problem with loading some of the pellets. Even the Falcon domes did it. If I held the rifle with the muzzle pointed up, sometimes the pellets would jam as I tried to close the bolt. I played with this for a while before discovering that if the rifle is held level it never happens. Just hold the rifle like you are shooting at a target and it feeds fine!

Loudness

Sorry to tell you this guys but this MAR177 rates a 1.8 on the Pyramyd Air loudness scale. It is one of the quietest air rifles I have ever tested. A Red Ryder is quieter, but not by much!

Summary

So far this old gem is performing well. It’s even better than I remember — thanks mostly to my Geissele trigger, but also to the efficient use of air.

The first accuracy test comes next. I can’t wait!