Monday, April 13, 2009

Determining optimum shot string size

by B.B. Pelletier

Lots of talk about the new Benjamin Marauder last week. In fact, it is the most talked-about PCP this blog has ever seen. Most of the talk has centered on accuracy and wondering whether the Marauder lives up to all the claims people, including me, are making for it. Well, on Friday, I had a very interesting phone call from Ray Apelles, the guy I told you was working on the Marauder with Crosman.

Ray's conversation boiled down to one point, "What is the criteria for determining the size of a shot string?" He clarified that by adding that he is interested in the accuracy at 50 meters (55 yards), which is the maximum distance in national and international field target competition. His reasoning is simple. The max shot string for him is always the most shots he can get from a charge and expect them to stay on the impact point at the max range. He defines "stay on the impact point" as giving a one-inch group or less. For Ray, any shot that won't stay inside the specified group is one he doesn't want in his effective shot string, because he competes in field target. He wants to know that every shot has a chance of hitting the target.

He then asked me what kind of velocity variation I would accept in an optimum shot string. When I answered 30 f.p.s., he explained that he didn't care about velocity, so long as all the pellets met his accuracy criteria.

A voice from the past
That took me all the way back to 1995, when I was first introduced to PCPs by Rodney Boyce. He taught me how to determine a PCP's performance curve with a chronograph, and how to relate those numbers to the pressure gauge during the fill. This is stuff we have been going over in the past several weeks, so you regular readers should know what I'm talking about.

Rodney then told me to select an aim point at 50 yards (this was in the days before the field target maximum distance was lengthened to 50 meters) and to shoot pellets within the performance curve (only those pellets going fast enough to make it into your optimum set of velocities) until they started to wander away from the group. The maximum number of pellets that stayed in the optimum group was the limit of usable shots for that particular rifle--no matter what the chronograph says.

Here's how it works
Let me give you an example. Say your chronograph suggests you have 31 shots that stay inside 27 f.p.s. maximum variation. You might be tempted, as I was, to call that your usable string. But if you also shoot a group at 50/55 yards, you may discover that after 21 shots the group starts to open up. Which number should you use?

Well, use 27 shots if numbers are all that matter to you, but use 21 shots if you actually want to hit what you aim at. See the difference?

...or, think of it this way
Here is how Ray said it. "I see your five-shot groups are all very tight. What would happen if you overlaid five of those groups on each other? Would the resulting 20-shot group be larger?"

Before you look at those four Marauder targets I posted last Friday, let me tell you that I adjusted the scope between them. Those were taken from 20 different targets I shot with the rifle, but there was some scope adjusting going on. However, Ray's call has raised an important question. Should I be trying to show you the optimum pellet spread based on group size instead of velocity variation?

This will add a lot of time to testing
It's far easier for me to do velocity variation, because all I have to do is pick a set of numbers from a larger set. To show optimum group size will mean many more hours at the range, because I will be shooting 20 to 35-shot groups, depending on the gun. And, because I won't know how large those groups should be before I begin, I will have to shoot several of them to find out. And all of that comes AFTER I have discovered a good pellet for the rifle!

Guns to be hand-held
You can tell me to just attach the gun to the bench with a vice, but that is impossible with the current equipment I have. The benches I shoot from are all movable, plus many of them are portable. Maybe I can have a heavy custom vice rig built for this, but at present I don't have what I need to clamp the guns in a vice. I will have to hand-hold the guns for now. I'm not complaining, but my groups will be a little larger because of it.

What about springers?
Now, if you are one of those people who wants everything in life to be "fair," you are no doubt thinking that spring guns aren't the same as pneumatics. What will I be doing about them? Well, I spent a good portion of the weekend thinking about this and my solution is to shoot 20-shot groups from every spring gun at 35 yards. I picked 35 yards because, even though there are RWS Diana 54s and TX200s in the world that can hold their own with PCPs, there are also Benjamin Super Streaks and Mendoza RM2000s that can't. And occasionally I'll pick up a rifle that can't even keep up with the average springer. With a 20-shot group at 35 yards, you will get to see the accuracy potential clearly. Obviously the velocity doesn't fall off at any point with a springer, but just as obviously to those who have experience with them, springers are ten times harder to shoot well than pneumatics and CO2 guns.

And CO2?
Speaking of CO2 guns, what shall I do about them? Well, there is the problem of temperature to consider. All my long-range shooting is done outdoors, and that will limit me to warm days without wind, only. I have decided to treat CO2 guns like springers and shoot 20-shot groups at 35 yards, but I will adjust this as we go. I will also pause between shots to allow the gun to warm up, and the amount of time in each pause will vary with the temperature.

Target guns will not be tested this way. Them I'll continue to shoot at 10 meters, because nothing else matters. And obviously BB guns will also not be included.

Only groups
There will be no more bullseye targets. Once I have sighted-in I will shoot at small aim points and the scope will be adjusted to group far enough from the aim point so I don't destroy it with my shots. I will also make reference lines on the targets to align the scope reticles, to eliminate the possibility of error from canting.

And don't expect to see me shoot ten groups like this, so you can see a relative size. That would take days of time that I simply do not have. You can certainly do it with your one or two rifles, but I test hundreds of airguns and there's no time for unlimited testing. While determining the optimum group size I will also get a feel for the rifle, so the group I do shoot will be based on that experience. If anything happens to spoil the group I will stop and shoot another and I'll tell you about it in my report.

I'm going to give this methodology a try. The last time I tried anything this ambitious I was shooting 10-shot groups while testing different versions of a Ruger 10/22 with many types of ammo, and it took days to get the test completed. This isn't that ambitious because I'll only be shooting a single type of pellet in one gun instead of eight different types of ammo in two different guns, but it's still plenty of work. The results should be more believable, though, because you will see clearly if the shots are migrating during the test. I think I will call this the Mega Test.

Marauder update
In a related note, Crosman called last week and offered to send me the very latest version of their valve for the Marauder. Since they sent my test gun 45 days ago they have continued modifying the radius and shape of the air transfer port and they have made a breakthrough that they say bumps the usable shot count upwards by several shots. It may also make the velocity variation tighter. When it arrives I'll install it and report the results to you. That will also be a good time for me to explain how to adjust the fill pressure level and the velocity adjustment, because I'll have to do both after completely stripping the gun.

71 Comments:

At April 13, 2009 5:58 AM, Blogger B.B. Pelletier said...

Vincee or anyone,

There is a Beeman C1 for sale on the Yellow Forum this morning. The C1 was the rifle that helped me develop the artillery hold. It is a handy carbine that has plenty of power and accuracy, and after 3,000-4,000 shots it becomes quite smooth.

The asking price is a little high. I would have liked to see $250, but you don't see C1s come up that often.

B.B.

 
At April 13, 2009 6:08 AM, Anonymous Vince said...

Hmmm... making more work for yourself, eh? Too much time on your hands, I guess...

For some of my own noodlin' around I had taken to doing 10 shot groups. What always made me wonder is this - what do I do when I've got one or two obvious fliers in an otherwise tight group? Ignore those shots and take them over on the assumption that I screwed up?

When doing 5-shot groups I had occassionally noticed (even at short ranges) a strange occurance... 1st group will be tight, 2nd group will be tight, but the POI would have shifted. I'm guessing it's a slight shift in hold due to the fact that I'm aiming in a slightly different direction. Or at least that's my guess.

 
At April 13, 2009 6:47 AM, Anonymous Anonymous said...

BB
now you're gettin really ambitious.
shooting from a bench instead of a vice is gonna test your endurance as well as your stamina not to mention the guns abilities.we really appreciate all you do for us,but that is seriously time consuming.I think most of us are willing to wait for you to spread this out as much as you need to cause I seriously don't know how you find the time!
Just really wanted to say thanx.I for one have learned a lot from you over the years and don't think I could have gotten lots of the info you provide anywhere else.

A very loyal reader
JTinAL

 
At April 13, 2009 6:54 AM, Anonymous Anonymous said...

To all
I don't know how many of you there are,so I'll just extend my thanx also to anyone who gives their time
to helping BB out.I'm not very PC
savvy, but I've got a pretty good internet connection and quite a bit of time on my hands so if there's
anything I can do to help BB out just let me know.

JTinAL
LOL word veri. is plede

 
At April 13, 2009 7:00 AM, Anonymous Anonymous said...

Vince
when shooting for groups I think it's better to always put your targets in as close to the same place every time as you can.
that eliminates shifting positions and possibly putting yourself in an unintentional strain.
this always helps what little consistency I have.
just my .02

JTinAL

 
At April 13, 2009 7:05 AM, Blogger B.B. Pelletier said...

JTinAL and Vince,

Maybe you are right. I won't know until I try it. I think I'll start with the Marauder and see where that takes me.

B.B.

 
At April 13, 2009 7:21 AM, Anonymous Anonymous said...

BB
I can't imagine shooting those long strings with multiple springers.
even just shootin fer fun pumpers and springers eventually get tiring.

I don't have the training or experience that you have,but I would imagine that CO2 and PCP would be less tiring especially with scuba tanks for refills.

Good luck anyway,I'm sure it will be satisfying to put all this together.I don't think anyone else has even considered it with
multiple guns to test.

JTinAL

 
At April 13, 2009 7:40 AM, Anonymous Rob said...

BB, In the post are you placing the super streak above your average springer or at average ? When do you plan to test a super streak in .22 caliber ?

 
At April 13, 2009 7:56 AM, Blogger B.B. Pelletier said...

Rob,

The Super Streak is an average spring rifle at best. I had no plans to test a .22, or if I did I forgot about it.

B.B.

 
At April 13, 2009 8:25 AM, Blogger Brody said...

B.B.,
thats some really deep thought there. I never would have thought of anything like that. You know as well as i do, not every five shot group will be the same as the last, so a 20 shot group is a good idea. Maybe i can do a couple other things on my blog like 20 shot groups in 20 degree temps, or 20 shot groups in 15 mph winds, and stuff like that. Now to another question i have. I want a fun plinking/hunting gun, but i dont want to spend a whole lot. I dont want to spend more than $200. I need it to have a high fun factor, so if its a springer, it needs to be easier to cock, and not that hold sensative, but at the same time i need it to be accurate. What would you say a good choice for this one would be? Im thinking a crosman 2260, or a crosman 2100. along with many other guns. i need it to be quite accurate as well. So what do you think?
Brody

 
At April 13, 2009 8:30 AM, Blogger derrick38 said...

BB,

I think your new testing plan could drive a normal guy to drink. I do think you nailed it on the head about performance at the target and not velocity variation at the chronograph. Certainly the additional shots could give a better overall picture of the rifle, but also (obviously) will be much more taxing to the shooter.

Derrick

 
At April 13, 2009 8:33 AM, Blogger derrick38 said...

On a somewhat related note, I'm getting really nice tight group sizes by reducing the number of shots I fire at each target. I was formerly testing with 10 shot groups, that shrank to 5--and I saw a dramatic reduction in group size. Carrying that further, I now shoot one shot and call it good.

Derrick

 
At April 13, 2009 8:40 AM, Blogger B.B. Pelletier said...

Brody,

The Hammerli 490 comes to mind.

B.B.

 
At April 13, 2009 8:41 AM, Blogger B.B. Pelletier said...

Derrick,

I have a perfect record of shooting one-hole one-shot groups! ;)

B.B.

 
At April 13, 2009 8:54 AM, Anonymous Vince said...

BB - a 490 for hunting? Isn't that a little underkill?

 
At April 13, 2009 8:59 AM, Blogger B.B. Pelletier said...

Vince,

Sorry about that! I read the plinking part and overlooked the hunting. Yes, a 490 is no hunting gun.

Brody,

I would look at a Gamo Big Cat and an RWS Diana 34 Panther.

However, all breakbarrel springers are hold sensitive, so maybe your 2260 is the best pick after all.

B.B.

 
At April 13, 2009 9:05 AM, Blogger Brody said...

Thanks B.B.,
Thats what i was thinking. I also looked at the Rws 34, because Pyramyd has a used one for $190 i think. I may get the 2260 and see what it can do, then up the anti, and mod it a bit.
Brody
p.s. I AM THE 1hole group with my red ryder baby.

 
At April 13, 2009 9:13 AM, Blogger kevin said...

B.B.,

Thanks for the heads up on the C1.

Your experimental shift in defining shot string by accuracy instead of velocity spread is wholeheartedly endorsed by me. For the little that is worth.

I know this will take significantly more of your time since pellet selection is critical and also takes an inordinate amount of your time in some guns. Nonetheless, since your priority for many years on this blog has been in testing new guns, what is more important in a new, untested, gun than accuracy? I, for one, would rather see you significantly reduce your time spent answering our questions, or eliminate answering entirely, in exchange for creating more time for you to do this thorough testing for accuracy that you're describing in todays post.

Here's my other two cents.

I've spent a lot of time in accuracy testing to determine a "short cut" for best pellet/accuracy. I test springers at 20, 30 and 40 yards. I test pcp's at 20, 30, 40 and 50 yards (don't have more than 50 yard range in town). This summer the distances for the pcp's will be increased to 100 yards. I think your 35 range for guns other than 10m is a great idea.

Here's my short cut. I use a fairly inexpensive, fully adjustable, hyscore shooting vise. I've modified the front and rear clamps with stiff foam for a more uniform clamp. This works great on pcp's but terrible on springers. For springers I use my old front and rear benchrest bags from the firearm days. The names are worn off so I can't tell you manufacturers but the front bag is nylon and rear bag is leather. I spread the "ears" flat on the front bag and place a big computer mouse pad (slick side up) on the front bag and put wax paper inside the "ears" of the rear bag to imitate your artillery hold as close as is artificially possible. With heavier/more powerful springers like the R9, adjusting the front resting place on the gun makes a differance in group size. Your freehand hold is probably as good as this setup for springers.

Without exception this has set the high water mark for duplicating group sizes off hand. It's also taught me many other things.

One example is that for pcp's I use the chrony to determine ideal fill pressure and would select my shot string using a velocity spread of 47 fps(based on your analysis of a AA S410 shot string Wayne provided you awhile back). What I learned is that this is a good guideline but not the whole story. The vise taught me that although the power curve on the fx tarantula said I would have 28 good shots over the power curve within a 47 fps spread, only 20-22 shots would group, with the best pellet, before opening up wildly. Conversely, the same analysis and same testing showed the AA S410 would get 30-33 shots at the medium power setting whereas in reality the poi does not shift until about the 55th shot (almost a 65 fps spread!).

PS-The mouse pad is critical for springer testing since my front bag has a "pebbled" exterior designed for gripping guns. Big mouse pads can be found at most thrift stores for $1.00.

kevin

 
At April 13, 2009 9:23 AM, Anonymous twotalon said...

B.B.
You must have been reading my mind. I have been meaning to ask you if anyone had defined what should be considered a good shot count.

It was obvious to me that total velocity spread as a fixed standard number was not going to get the job done. What looked best to me was to establish how many shots would stay in the kill zone at the desired shooting distance. Of course, the size of the kill zone has to be established by the shooter.

twotalon

 
At April 13, 2009 10:20 AM, Blogger derrick38 said...

Brody,

The 2260 has excellent accuracy potential. The steel Crosman breech is an immediate upgrade must. I've currently got a Leapers Bug Buster 6X in Accushot rings on mine. There are tons of upgrade and custom part options for the gun as well.

If you need the power for the price, look here: IZH MP 513M in .22 cal.

http://www.pyramydair.com/s/m/gun/443

I've yet to shoot a gun from Baikal that didn't group well.

Derrick

 
At April 13, 2009 10:24 AM, Blogger CJr said...

Sounds like we're going to get another very valuable piece of info here for no effort on our part (I guess mouse clicking can be difficult for some). What did we ever do to deserve such goodness?! BB, what ever you do during this test, you are guaranteed an enthusiastic, appreciative audience.

You also got me looking at the Yellow (dang it!). The good deals don't last very long there do they? Being a newbie, I'm curious what BOI means. It appears important but I've never heard it before. It sounds like something sellers need to be or their integrity is in question. And how does one get on the BOI?
-Chuck

 
At April 13, 2009 10:40 AM, Anonymous melloroadman said...

I have learned to increase my string count as I believe most have by starting off with about a 1/4 inch hold under with a 6 oclock poa and ending with a 12 oclock poa at 50 yards . So I guess what I am saying is I think you have created a lot of extra work for your self . The basic chrony readings should give a shooter his starting point and then his skills and knowing his rifle should give hin his shot count IMO . Marvin

 
At April 13, 2009 10:59 AM, Anonymous BG_Farmer said...

BB,
This is one of those posts that makes me glad I've only got springers:). I think it will stay that way until they make a PCP that has 80 optimal shots from full fill.

An, e.g., 1800 psi regulator combined with higher fill pressures would seem to be the answer to making PCP's easy to use. For the hard cases, such as FT participants, shot strings, fill pressures, and valve lock may be fun, but not for me. If I want frustration at longer ranges, I can always mix random lots of .22's.

 
At April 13, 2009 11:05 AM, Anonymous Herb said...

BB,

Sorry to post a half ass answer, but I'll have to think about a "good" answer for a couple of days. By then the herd will have moved on to an entirely different topic.

First of all I think that PCPs are so accurate that the shooter is a significant factor. My hands shake, I don't have very good technique and so on. So if I could keep shots inside 1/2 inch at 20 yards I'd be thrilled. That level of performance would no doubt dismay others.

There are always fliers that happen for whatever reasons.

Shooting groups leaves information on the table. The best analysis would be to measure the x-y position of each shot relative to the aim point and use standard deviations.


Using ChairGun2 here are some numbers. Starting muzzle velocity, drop @ 50 yards, muzzle velocity at 50 yards for Crosman premiers 14.3 grain, BC 0.0190. These numbers are roughly what you were getting for the Shamal a couple of articles ago.

810, 8.357, 582
800, 8.567, 575
790, 8.785, 568

Of course the numbers are different at 10 yards. So how far you want to shoot makes a difference too.

Back to analyzing the numbers, the 20 FPS difference results in a POI shift of (8.785-8.357) or 0.428 inches at 50 yards. If you're shooting 1 inch groups at 50 yards, the vertical stringing won't be too noticeable. If you're shooting 0.25 inch groups at 50 yards, then the vertical stringing will be obvious.

There are statistical techniques to compare variance (standard deviations). Perhaps the way to analyze this is horizontal error vs vertical error.


All in all the overall point is that the effort to analyze the data ought to be somewhat commensurate with the effort put into the shooting. Using groups is OK for quick and dirty shooting, but a more detailed mathematical analysis is needed to really pick the problem apart.

Herb

 
At April 13, 2009 11:10 AM, Anonymous Rob said...

So, if the super streak is nothing above your average gun except in power, Can you recommended a spring gun that can kill Crows and other birds are a fair range ? the only guns that seem to gain my interest are the Walther falcon and the rws side levers.

 
At April 13, 2009 11:53 AM, Blogger kevin said...

Chuck,

Re: Yellow classified ads

boi is short for Board Of Inquiry. It's the equivalent of "feedback" on ebay. The way you get on the boi is by purchasing or selling something and having the other party put your name and their opinion of your performance during the transaction on the boi page.

kevin

 
At April 13, 2009 12:10 PM, Blogger CJr said...

Kevin,
re: Board Of Inquiry
Thanks for that.

Did everyone get to see Harry-aka-Deadeyedick-from-the-Uk's comment in the Benjamin Marauder - Part 3 post at 10:14 this morning? If not you should. It's a good piece from a well grounded sounding young man.

-Chuck

 
At April 13, 2009 12:18 PM, Blogger ajvenom said...

An easy to pump multi pump that hits hard for it's class is the daisy 22SG. I added 4x32AO leapers scope and it's a tack driver under 35 yards with jsb express or gamo mag points. A benji muti pump will hit harder, but also harder to pump and more expensive.

I polished, lubed and installed a grt-iii trigger on a quest 800x .22cal with one piece scpe mount and leapers 4x32ao scope. Plenty of power. 3 years and approx. 10,000 shots and still getting better all the time.

For a springer now I would recommend a rws 34 striker or panther. Both good values for springers.

 
At April 13, 2009 12:56 PM, Blogger kevin said...

Chuck,

Completely agree with your take on the young man from across the pond. If we had more 17 year olds with his experience and insight we wouldn't have to worry about our future.

kevin

 
At April 13, 2009 1:56 PM, Anonymous Anonymous said...

B.B.

All that shooting sounds like fun. But why are you shooting the long strings with springers and CO2 guns? They have no power curve, and I think everyone concedes the accuracy of pcps over both categories. For the other two I'm guessing that CO2 has the advantage if you watch the temperature which isn't really a question of shooting skill.

B.B. and Vince, you're amazing. I did a few rapid dry fires with my 747, and the problem is cured. It shoots like a new gun. So, how does that work? I don't see how dirt on the seal which is evidently the problem could cause a leak in an intact seal. B.B., you ask all the hard questions. I was just thinking it might be time to adjust the piston head. The fact is that I have not adjusted it since our last conversation and my disastrous start with this gun a year or so ago. After getting the lever to behave correctly, my impulse was to let well enough alone, but it's time to revisit.

Chuck, I've found follow-through to be vitally important for spring guns for a reason I read about from Robert Beeman. Airgun pellets dwell in the barrel much longer than bullets in firearms, so you have to preserve your shooting position as long as possible. Then, the question becomes what exactly is follow through. You cannot harden up to anticipate recoil, especially not in springers, and you can't go limp. Trying to preserve every aspect of position is hard to do. What I've found works for me comes from a couple of incidents in my lackluster shooting career of long ago. While spraying bullets all over the target from a standing position at 50 feet, there was one particular shot where my eye happened to rest on the target through the recoil, and, behold, it was on target. Another time, I was at an army rifle range shooting an M16A1 at all ranges with little effect. For fun, I thought I would aim at the 300 yard targets at maximum range, and again by happening to rest my eye on target through recoil, it went down. Even the mildly contemptuous army instructor was impressed. So, I've tried to systematize this technique. The idea seems to be that where the eye goes, everything else will go to; the eye will tell the body just how to react to keep the shot on target. This sets up some complications with the theory of locking on to the front sight while shooting; it requires moving from the front sight to the target as the sights jump around. But this seems workable. Anyway, that's my experience.

Deadeyedick, thanks for your response. That's more data to file away about the SA80. I was under the impression that firearms were not allowed at all in the UK. But even such access you have is still pretty different from the U.S. The Civilian Marksmanship Program (CMP) sent out a long note about the unusual restrictions they will have to impose on ammo sales because of demand. They are now limiting customers to 2000 rounds of 30-.06 per year....

Matt61

 
At April 13, 2009 2:05 PM, Blogger ajvenom said...

Thanks again Harry, you shoud tell tham about your cadet training and some of your range outings.

All the shooters who I have met, who generally love the sport, have been good people from all ages and all walks of life.

Would be nice if there was a list of most current blog titles as people commented on them. BB manages to catch new comments on old subjects, but hard for others to sse.

Also, I kinda miss the old listings on the airgun areana page. The simple, easy to use and complete list on the main page is gone.

 
At April 13, 2009 2:09 PM, Blogger B.B. Pelletier said...

Matt,

As I have written many times a 5-shot group is not a true representation of aq gun's accuracy. Nor is a 10-shot group, though it is much closer.

Since you know why I'm doing the PCP, let me tell you that if I do larger groups with spring and CO2 guns we will all have a clearer picture of their true accuracy. To be statistically significant to the farthest degree possible, I really should be shooting them 30 times, but I am fudging, because a 20-shot group is REAL close to what you'd see from 1,000 shots.

B.B.

 
At April 13, 2009 2:42 PM, Anonymous Vince said...

Brody, I might have a gun for sale that might do OK for you. Email me at vfblovesnancy@yahoo.com if you want, and I'll give you the details.

 
At April 13, 2009 3:43 PM, Anonymous Anonymous said...

Vince,


If I recall, Brody is a minor.

 
At April 13, 2009 3:47 PM, Anonymous Airdog said...

BB - off topic question: I know you've always raved about the AA TX200. I always thought it was a 12 foot pound gun, which made its smoothness understandable. Now I see they're listed as shooting 930 fps in .177. Is this a FAC version, and will it shoot as smoothly?

 
At April 13, 2009 4:00 PM, Blogger B.B. Pelletier said...

Airdog,

My TX shoots 7.9-grain Premiers at 933 f.p.s. That's over 15 foot-pounds.

The 12 foot-pound TXs I have shot have all be a little on the jerky side, with a harsh piston slap at the end. Harsh for a TX--which is smooth for the rest of the world. All my TXs have been FAC.

B.B.

 
At April 13, 2009 6:01 PM, Blogger Brody said...

Vince,
i will email in a bit.
yes i am a minor, but that doesnt mean i cant order a gun from someone. My dad could order it for me, or i could send him a check or something. But thanks for pointing it out.
B.B.,
Could the vibration from my Crosman Storm XT be trowing my scope off zero? B/c im constantly rezeroing.
Brody

 
At April 13, 2009 6:19 PM, Blogger Rusty Barrel said...

B.B.
Sorry to be off topic.
I have been in the shadow of your blog since January. I am the ANON guy who knew the guy in Saskatoon with the "gravity gun" April 1st. I'm a Boomer who grew up in the JFK era. My first rifle was a FWB124 in '78. My friends had Sheridans, I shot a laser beam. I let someone borrow it and they both dissappeared. A lesson learned.
Thirty years forward....I am rekindling those interest and started my revival with a new LD pistol and a modified 392. As you might guess, I prefer American. I don't hunt, but the 392 takes care of my pest problems quite well. I am wanting one more rifle, but I am stuck in springer/PCP limbo. I believe you are a big fan of the Talos SS. I am also closely looking a the Discovery and Marauder.
Sadly, I live rural with no airgun clubs to be found. But my yard allows easy and safe fifty yard shooting. I probably shoot as much bench rest as off hand. B.B., I'm high mileage and I want to make my hobby easy on myself. Your opinion on a rifle to enhance my experience will be appreciated.
By the way...Your regular readers with the info they share really enhances your blog. I would like to get to know them as time goes by. Keep up the good work.

Rusty Barrel.

 
At April 13, 2009 6:42 PM, Blogger ajvenom said...

I use an average of 4 to 5 five round groups.

As for the Ted Williams version of the 880, it needed some lubing. Good ole pelgun oil to be safe. Took a few shots to get the power up. I'd say it hits about right. It's power is between a 1377 and a 2100. As for groupings, RWS Superdomes hit about the best so far at 12mm (.472) avg ctc at 10M.

Good points on the TW 880, I like the spring latch on pumping lever, it's more quieter and smoother than my 22sg model. Pumps real easy and continued to hit harder up to 12 pumps, but 10 is recommended and groupings are better. Molded cheek pad isn't bad for right handed shooters. The brass metal receiver looks sharp. Wasn't sure if it was scopeable, but it does have a 11mm on the receiver.

The downfalls are you have to becareful incase a BB loads that may be in the resevoir, even if it seems empty You can forget long pellets and becareful not to pull bolt back too far when loading pellets because they have a tendancy to fall back into BB resevoir.

Well, it's going to be a present for a freind of mine, who is just returning to airguns. He's had some bb guns as a kid, so I am hoping he'll like this one.

 
At April 13, 2009 6:42 PM, Anonymous Anonymous said...

B.B.

Yes, I remember the statistics conversations. I'll be interested to see the results of the tests, and I suspect they will be unique. I've never heard of anyone doing accuracy tests of 20 shots and more. The notion of absolute accuracy brings up an interesting philosophical point. It seems to me that accuracy in concept has some comparison built in. The problem is that it is so exhausting to compile data with 20 shot groups that this can't be done with more than a small subset of guns, and it will then be hard to compare them with other guns for whom only 5 shot groups are available. As part of such a comparison, I suspect that a low shot number would color one's impression in a way that is hard to compensate for. It would also be interesting in the test to see how group size relates to pellet size. Some remarks from before indicate that it is not a linear relationship as in a three shot group will generally double with five shots and a 10 shot group will not drop to half with 5 shots. Anyway, you may as well get all the data possible from all this work.

Rusty Barrel, with 50 yards available who needs an airgun club? You can attend B.B.'s field target seminar and start your own club. I'm curious what you mean by "high mileage." If it means you don't want hassle, I can identify with that. If I were you, I would get a...Marauder. That consistent accuracy, multi-shot magazine, and shrouded barrel really set it apart for me. B.B., by the way, with the reports on the Marauder, I am getting greedy. Reports on the Crosman Challenger and Air Force Edge are welcome anytime.

All, duct seal has been vanquished. I've managed to shoot a clear hole through about two inches of the stuff.

Matt61

 
At April 13, 2009 6:42 PM, Anonymous JC said...

BB,

Wow! To be here at the start of a new era! How many years have you been testing; and now this major change in your procedure. I'm awe inspired; good luck with the new approach (but I will still be trying to wipe out my aim point).

Brody,

The RWS is sweet and has a lot more power than a Co2 gun. AND you can shoot it in the winter if you want to.

If you are stuck on C02, the Hammerli 850 offers the most in that price range and is still plenty accurate.

The 2260SE gives you the steel breech and a bug buster scope for not much more than the individual parts if you want to stick with the 2260. My wife has a 1760se and its a nice little gun, but it was purchased with smaller size/lighter weight in mind.

 
At April 13, 2009 7:25 PM, Blogger B.B. Pelletier said...

Rusty,

I understand. For accuracy and overall ease get the Marauder. For economy, get the Discovery. For power with accuracy get the Talon SS and get an optional 24-inch barrel.

If you like bench shooting the Marauder is your cup of tea.

B.B.

 
At April 13, 2009 7:26 PM, Anonymous Vince said...

Brody, I've also had consistency problems with the Crosman Quest variants. I've had several of them, and they also seem to be more hold sensitive than the Gamo rifle they copy.

The gun I've got available is a Cometa-built RWS 92. Perhaps some of our bloggers have experience with this rifle and will post their own comments.

 
At April 13, 2009 7:53 PM, Anonymous BG_Farmer said...

Rusty Barrel,

You're better off with even 25 yards at home than 100 yards at some club you can only get to once a week at most, so you are going to be just fine. Get whatever BB tells you and you should be happy:).

 
At April 13, 2009 8:01 PM, Blogger CJr said...

Matt61,
You didn't say how you shot through the duct seal. Was it one shot and if so with what? Was it erosion over time after many hundreds of shots?

I bought out all the duct seal in town. I cleaned out Lowes, Menards and Home Depot. It's been over a week now and they still haven't restocked. When they do I'll probably make the rounds again. I'm sure there is a stocking clerk somewhere scratching his head over the sudden disappearance.

BTW, a while back our friend Jane mentioned Law Enforcement rubber panels for a pellet stopper. I tried it and I get ricochets back at me at least half way. My little springers and 953 are not strong enough to penetrate. I haven't tried the AirHawk yet, it's still out on loan. I'm very afraid to though. If 900 fps doesn't penetrate I'll get a knock on the noggin. It was cheaper and larger than buying duct seal for the same job but alas no workie. It is advertized to absorb 9mm bullets. I guess I just need to shoot powder in my basement or teach my little ones how to diesel (Ha Ha).

-Chuck

 
At April 13, 2009 8:04 PM, Anonymous BG_Farmer said...

Chuck,
I assume Matt used his 2000 rnd. CMP quota of .30-06 to put that hole in the duct seal:).

 
At April 13, 2009 8:12 PM, Anonymous gubb33ps said...

It’s going to be a devil of an undertaking to do this right. After all, when shooting a 50 shot group, only TWO shots really count (the farthest apart). The other 48 shots are pretty much ignored.

(Could review the old-time Black Powder method of “string measure”...which makes measuring groups a lot more difficult, but might be the better system.)


First off, the rifle has to be both consistent enough in POI and accurate enough to make shifts in group centers meaningful. A rifle that can only manage 2”” groups masks a 1/2” shift in impact pretty well... a super accurate one that is prone to shifting it’s POI leaves you guessing if that 1/2” shift is due to vel. drop off of just one of it’s random shifts.



Benching springers make it a little worse as we all tend to get tired after 50-60 rounds of intense concentration (like you’d do for this test) and that leads to variation in the shooter’s hold.

Accurate “recoilless” guns (OK...Newton’s laws still apply, but we tend to call them recoilless anyway) have been the easiest to get useful, repeatable, data from.

Looking forward to the results...but think you might have more work cut out for you than you first guessed.

 
At April 13, 2009 8:14 PM, Blogger ajvenom said...

And if you're addicted to airguns.....get them all!!!!

I recommend the Crosman Discovery. Nothing compares to the Discovery and has a greater value. So check out the Discovery. Discover one today.

ok Josh, your can send me a free Discovery now. Just kidding.


You should have Joshua Ungier as a guest/host blogger. We would love to hear about his airgun experiences. Also, any tips on starting your own business would be cool too.

 
At April 13, 2009 9:41 PM, Anonymous Anonymous said...

gubb33ps,

RE: "It’s going to be a devil of an undertaking to do this right. After all, when shooting a 50 shot group, only TWO shots really count (the farthest apart). The other 48 shots are pretty much ignored."

BB has two chances of shooting 50 shots without a flier - slim and none. That is why the X-Y analysis should be calculated and a standard deviation used.

Herb

 
At April 13, 2009 11:24 PM, Anonymous Mr B. said...

B.B.,

Thanks for all the effort you're going to be putting into the accuracy testing hence forth. Herb's idea of the X and Y axis sounds interesting to me. Military has formulas for doing that now, I do believe.

CJr,

Try shooting your SS with both eyes open. No eye strain. When I'm in the zone I can see the pellet hole appear in the paper target or watch the splash/flash the pellet makes when it hits a metal spinner. Cool stuff and I know where that hole is going to appear in the paper. However, if I really start to think about it, it'll be gone. Try it for a while and let me know if it helps.

Mr B.

 
At April 13, 2009 11:24 PM, Anonymous Anonymous said...

One Shot Groups
Colonel Cooper wrote an article many years ago about one-shot groups. Basically, he said you pick up the rifle and fire one shot. Then measure the distance between the aiming point and the shot. He called this distance "inital radial dispersion." Next day, try again. The goal is to make your "dispersion" as small as possible. This is a test of the shooter, more than a test of the rifle. Or really, a test of how well the shooter knows the rifle.
--MikeU

 
At April 14, 2009 12:23 AM, Anonymous wayne said...

B.B. & all

I just got back from a delivery and meeting to Portland.. I see no one has been a "pain in the ass" for me while I was gone.... Just can't get good help these days..

anyway...

That sounds like a great plan for testing!

Might I suggest that maybe we could split up the test with the blog members... We could all shoot the guns we know and shoot best, with their best pellets.

One problem is posting the photos on this blog for the comment posters..

or.... maybe each one could be a blog! (Tom, that would get you off the hook for awhile, so you can do the TV show!)

It would also be cool to check one AAs410 .177 against another or .22 vs .177... one disco vs another, one USFT vs another!!

It just seems like the info would be more diverse, and become ready sooner...


Brodi,

The RWS 92 is a very nice mid size or large "youth" springer that shoots a 8.4 JSB at a perfect 675fps or so.. pretty darn accurate too! It's one of the few springers I kept and still buy!

I don't think it can be beat for the money.. nice trigger too!

Wayne,
Ashland Air Rifle Range

 
At April 14, 2009 5:41 AM, Blogger B.B. Pelletier said...

Brody,

Parallax error (where you place your face on the stock) can be just as big a problem as the scope. I doubt the scope is your problem.

Breakbarrel spring guns are the most difficult to shoot well. You must learn the artillery hold and do it perfectly to get accuracy:

http://www.pyramydair.com/blog/2007/07/artillery-hold.html

B.B.

 
At April 14, 2009 5:43 AM, Blogger B.B. Pelletier said...

gubb33ps,

I may have bitten off more than I can chew. Time will tell. I'm going to shoot my first group today.

B.B.

 
At April 14, 2009 9:30 AM, Blogger CJr said...

Mr B,
My SS is down for the count right now with a bad CO2 adapter. PA should be getting it delivered from UPS today to confirm that. I miss my Talon. Shoulda had air for backup. Or is it the other way around?

I have shot with both eyes open, as you say, and I prefer to do it that way. However, I noticed that when I feel like I need to concentrate harder, I shut the non-shooting eye. Old habits. I think, like in golf, the brain can only handle three conscious commands. The rest have to become automatic through practice.

The beauty of the SS is now I know I can be accurate, too. I'm talking one holers, when I'm alone, on my indoor range, 10m, and under no pressure. And I know my pellets are accurate, too. I'm currently using Meisterkugeln (8.2). I've ordered a box of Crosman Premier Heavy (10.5) because BB says to use the heaviest pellet in a PCP or CO2 gun plus he likes these, so I'll see if I do too.

Mr B, the follow through does work for me, so thanks for the reminder. I shot some nice 1/4" groups with my IZH-61 and fused three pellets together on at least one occasion.

The duct seal is great for measuring pellet spread. If I clean out the previous shot pellets, I have a clean area to measure. After shooting, I remove the target and behind it are the pellets embedded in the pug. Most of the pellet skirts are flush with the surface and easy to measure, easy to dig out and see them when they're fused together.

-Chuck

 
At April 14, 2009 10:57 AM, Blogger Rusty Barrel said...

B.B.
Thanks for putting things in perspective. You cut quick to the chase. Although all that scub-dooba gear has its benefits, it is a bit much for me. I don't think I would be adverse to a low preasure PCP using a hand pump.

Matt61.
High mileage refers to some physical limitations that comes with the onset of "Old Timers" syndrome. You're correct to think that I am not looking for hassles or to work extra hard while having fun.

BG_Farmer.
You are absolutely right about the everday backyard experience.

Thanks to all.
Rusty Barrel.

 
At April 14, 2009 12:26 PM, Anonymous Scott298 said...

B.B.--Scott298 checking in. The rws 350 in .177 has always been advertised as having the flatest trajectoy of the magnum springers, why not put it in the group you intend to use. If you don't have access to one I'll lend you mine. Also if you find yourself short on scopes I've got a couple of brand new leapers-3x9 & 6x24. Let me know if you need to borow anything-Scott298

 
At April 14, 2009 12:51 PM, Blogger B.B. Pelletier said...

Scott,

Thanks, but I'm not looking for new guns to test. I have more than enough right now.

B.B.

 
At April 14, 2009 2:34 PM, Anonymous Mr B. said...

Rusty Bucket,

Like your name, it's very discriptive and also fits me. However, even though I am 6'2" and 148lbs, I am a pumper when it comes to filling the PCP's.

I have the Discovery and Talon SS both in .22. The SS has become my go to gun 90% of the time. I seem to get a tighter group with the SS and it's shroud is much quieter than the Discovery's LDC. However, my 19 year old son likes shooting the Discovery.

Before it'a all over though I will be adding a Marauder to my collection:).

CJr,

I feel you CO2 pain.. My Disco's pump took a dump last winter and I had no way to shoot cause it was too cold for the CO2 to work.

Mr B.

 
At April 14, 2009 4:02 PM, Blogger CJr said...

Mr B,
What is the minimum operating temperature you've experienced with CO2?

The Marauder is on my Rusty Bucket list, too. :)

-Chuck

 
At April 14, 2009 4:47 PM, Anonymous gubb33ps said...

Maybe not more than you can chew...but a lot more chewing than expected.

A pretty good argument can be put up (and has been by some in the firearms ammo industry) for 7-shot groups being the "best bang for the buck" when evaluating their products.

For shot counts, think you'll find there isn't going to be a simple number. May be a short equation that includes the volume of the air tube, pressure level, the level of consistency required, and the power level.

You're going to have fun with this one...expect a lot of comments (positive and negative).

Robert

 
At April 14, 2009 9:55 PM, Anonymous Mr B. said...

CJr,

Coldest temp with CPO2 maybe 55-60 degres. Not much good then.

Mr B.

 
At April 15, 2009 11:40 AM, Blogger andreas said...

B.B.,

Do you remember the talon 60 shot testing you did for me? That took a lot of time even without aiming the rifle. That data was really informative though.

A 35-40 shot accuracy group for the marauder would be very valuable information - with the new refined valve installed. If you could do that, it would be great. Looking forward to it.

We all appreciate the time you put in for the data you give us... all the afternoons you spend for your readers.

I also have a question: What's the best 50-yard springer after the TX200 and the Diana 54? Are those two far ahead of the rest?

Thank you
Andreas

 
At April 15, 2009 12:00 PM, Blogger B.B. Pelletier said...

Andreas ,

I may not be able to answer many questions in the future. I am going to be the co-host on a television program about airguns and my time will be very limited in the future.

The TX 200 and Diana 54 are well ahead of all other spring rifles. The Weihrauch HW 77 and 97 are the next best.

B.B.

 
At April 16, 2009 3:23 PM, Anonymous Anonymous said...

I tried to test BB's idea of 20-shot groups yesterday, outdoors at 50 feet with a lot of intermittant wind (which probably skewed the results). I'm not a great shooter, but I did have a pretty good rest and got consistent sight pictures.

My Crosman 1377C with a red-dot sight surprised me pleasantly with a .75 inch group shooting Crosman Premiers.

My Daisy 953, scoped, which I thought would do well, disappointed me with a 1.25 inch group, shooting Gamo Match pellets, and 1.5 inch with Daisy pointed pellets.

I may try this again on a less windy day or at the indoor range, but it was interesting to keep pouring shot after shot at the same target. Made big holes in the paper!

 
At April 16, 2009 10:27 PM, Blogger CJr said...

Anonymous Tester,
Try Meisterkugelns (8.2) in your 953 on your next test.
-Chuck

 
At April 18, 2009 8:34 AM, Anonymous Anonymous said...

Chuck:

I'm the tester.

Thanks for the advice--I'll give them a try.

I've been experimenting with Gamo round balls lately, which I got originally so I could feed my Daisy 890 easily (the feed tray is to small for my biggish hands).

To my surprise, the ball ammo is almost as accurate as pellets at relatively close range indoors.

I've tried them in all my airguns with the same result.

From reading this forum for a long time, I would have thought otherwise.

Purchawk

 
At April 21, 2009 11:12 AM, Anonymous Anonymous said...

B.B.

I'm a 34yr old pilot that hasn't fired a rifle down range since my 10th grade JROTC class. I recently purchased a Crosman Quest 1000 to take me back to the happy place I recall the range was for me. Many things you talked about in old blogs I found on the web helped me thru the 1st 50rds I've fire, is their any advice for do's and don'ts with my new rifle.

Thanks,
Wings.

 
At April 21, 2009 11:15 AM, Anonymous Anonymous said...

Mr B.

Thanks for the heads up.

 
At April 21, 2009 11:44 AM, Blogger kevin said...

Wings,

Welcome! Congratulations on the new Crosman Qwest 1000.

Several suggestions to increase and preserve the enjoyment of shooting and owning your new airgun.

Since improving accuracy in our guns is usually number one priority I would suggest that you try more than one type of pellet since accuracy varies from brand to brand and within the same brand. Since the Crosman Qwest 1000 is a relatively powerful gun try the heavier .177 caliber pellets like the crosman premier heavies in the cardboard box and the beeman kodiak pellets. See here:

http://www.pyramydair.com/s/p/pellet/154

and here:

http://www.pyramydair.com/s/p/pellet/296

I'd also recommend jsb pellets:

http://www.pyramydair.com/s/p/pellet/388

If you've read some of B.B.'s articles you've probably already heard about the "artillery hole" that is a very important technique to learn if you want all the accuracy from your gun that it is capable of. See here:

http://www.pyramydair.com/blog/2007/07/artillery-hold.html

For maintenance of your gun, DO NOT CLEAN THE BARREL unless accuracy diminishes. Many airgun barrels never need to be cleaned. If you feel you need to clean yours in the future please search this blog for "barrel cleaning". It's a technique unique for airguns. Improper barrel cleaning with the wrong products can ruin your gun. Like a firearm, wipe down the metal after shooting with a silicone impregnated cloth or with a good gun metal oil. I like ballistol.

Lastly, you posted your question closer to todays blog than your original post under an article B.B. did in 2005 but you're not on the current blog yet. All the links I've given you and the next one need to be copied and pasted in order to get to those sites. This link will always take you to the most current article that B.B. has written (B.B. writes a new article every day, Monday-Friday). When you get to todays article, go to the bottom of that article and click on comments:

http://www.pyramydair.com/blog/

Look forward to seeing you there!

kevin

 
At April 21, 2009 10:41 PM, Blogger B.B. Pelletier said...

Wings,

You have been well cared-for by a couple of our veterans. I'm traveling right now and have to answer these messages in the evening, after working all day, so my time is limited.

Please do join us on the current blog and keep on shooting that new rifle!

B.B.

 

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