by B.B. Pelletier
Part 1/blog/2009/06/crosmans-new-nitro-piston-short-stroke-part-1/
Today, I’ll look at the velocity of the new .22 caliber Crosman Nitro Piston Short Stroke breakbarrel rifle. There was a lot of interest in part 1, and I see that a few other writers are starting to test the guns, as well. So far, the interest seems to be all positive.
Cocking effort
I measured the cocking effort by pressing the muzzle down on a bathroom scale and breaking the rifle to the cocking point. This was a tricky rifle to measure, because if I went fast the effort increased by 8 lbs. If I went slow and deliberate, the rifle cocked with just 30 lbs. of effort through almost the entire cocking stroke. It actually falls off by a few pounds toward the end of the short stroke. As the shooting continued, I found that I was cocking faster every time, so I’m not so sure the slow part really does anything useful, but the deliberate part sure does!
So, there you are! Cock a gas-spring gun slowly but deliberately, and it’ll be lighter than if you try to horse it. By deliberately, I mean don’t mess around. Hold your hand as far out toward the muzzle as possible to get maximum leverage, which isn’t difficult considering that there’s no front sight. Once you start the cocking stroke, don’t stop.
Crosman Premiers first
The 14.3-grain Crosman Premier averaged 712 f.p.s. The spread went from 695 to 727, so a total of 32 f.p.s. Premiers loaded easily and flush with the breech. The average velocity develops a muzzle energy of 16.1 foot-pounds, making this pellet the clear power champion of the test
RWS Superdomes
RWS Superdomes weigh 14.5 grains and are pure lead pellets. In the Nitro Piston SS, they averaged 694 f.p.s., ranging from 680 to 709, for a spread of 29 f.p.s. The loaded easily and fit the breech well. The average velocity generated a muzzle energy of 15.51 foot-pounds.
RWS Hobbys
RWS Hobbys screamed out the muzzle at an average 771 f.p.s. At a weight of only 11.9 grains, these pure lead pellets generated an average energy of 15.71 foot-pounds at the muzzle. The velocity spread went from 761 to 781, for a total of 20 f.p.s., which was the second-tightest of the test. They loaded easily but were the tightest pellets in this test.
Air Arms domes
Air Arms domes are supposedly 16-grain pure lead pellets, but my scale says these weigh 15.9 grains. At that weight, they averaged 673 f.p.s. out the muzzle for an energy of 15.99 foot-pounds. The spread went from 664 to 679 for a total of just 15 f.p.s.–the tightest of this test. They fit the breech loosest of all pellets used in this test.
More on the trigger
I have to comment on this trigger, as it is one of the nicest I’ve seen on what is essentially a budget breakbarrel. It is two-stage and so crisp and positive! The second stage on my test rifle breaks at a repeatable 3 lbs., 12 oz. and is so crisp that I guessed it was a full pound lighter. If you like nice triggers on your rifles, you should like this one.
Just for fun, I adjusted the screw a full turn in each direction, but the only thing that changed was the length of the first-stage pull. The pull-weight remained constant. The second stage was also mushier after adjustment in either direction until several shots had been fired. Then, the crispness returned.
I also praise Crosman for leaving the safety manual. Nobody likes or needs an automatic safety. The safety on the NPSS works so smoothly and easily when you want it, yet it never forces itself on you. If I’m ever asked to testify about how safe I think automatic safeties are, I will say that I think they’re dangerous. They foster practices where a shooter cocks and loads the rifle, then immediately takes the safety off. I would rather have the responsibility of putting on the safety left up to the shooter, because they know when they need it and when they don’t. An automatic safety makes them take the safety off automatically without thinking. So, it might as well not be there.
This will be a fun gun to test for accuracy because it shoots so smoothly!
I don't know about others, but my automatic safety dosen't automatically make me take it off safe. But it does foster a situation where one assumes it's on safe, when it could fail. From SavageSam
I think Sam has a good point. In many guns all the safety does is prevent the trigger blade from moving. But if a trigger mechanism fails the sear can trip and fire the gun even with the safety on. Had it happen to me twice. The safety DOES lend a false sense of security.
I remember somebody – was it Robert Beeman? – who opined that safeties were not a good idea at all, and that they shouldn't even be installed on sporting guns.
I believe he also said that their only legitimate use was in combat situations, where it is a virtual necessity to carry a gun while it is cocked and loaded. Under those circumstances the safety lessens the likelyhood of an accidental discharge while still permitting the gun to be fired quickly.
The best safety is between the ears. From S.S.
There is no way I can afford to buy the disco, the marauder, the pneuma and the nitro… so many great rifles so little money.
Anyone needs a kidney ?
An automatic safety on an air rifle seems a bit pointless to me, especially on single shot guns like the Talon. A pellet gun is not going to be used for self-defense, unless you're worried about killer squirrels (and if you are, you'd probably get a repeater…) and if you're using it for hunting, you plan on shooting within a relatively short time frame.
As for target rifles, I can't picture the safety being used at all when the rifle is loaded.
Just my two cents,
Jake
Note: Just took a look at one of the Beeman guns. An automatic safety on a breakbarrel? Seems a bit rediculous.
The only merit for an auto safety, in my mind, is prevention of the trigger getting hit during pellet loading.
I hate an automatic safety also.
Safeties are removed from both Talons. They were a pain anyway.
A straight manual safety that can be clicked on or off is the only kind I like.
twotalon
Interesting points of view on the auto safety. I appreciate it on my RWS', taking the rifle off safety when my rifle is pointed on target and then putting my finger on the trigger as I steady the rifle in preparation for shooting. Vince makes a good point that the safety only blocks the trigger, and it's a plastic molding on the RWS' while Savage Sam is absolutely correct – the best safety is between the ears.
J-F, I share your misery. The tuition for U of MD for my daughter is fast approaching – another air rifle purchase will involve some real creative financing. Oh, and don't forget that 10M rifle Crosman should be releasing in the next month or two!
Yesterdays blog post seems to missing from the list.
Everyone,
I can't help but be very impressed with Crosman's recent air gun introductions. They seem to be one of the few companies that are listening to airgunners especially experts like B.B.
Speaking of B.B., when I clicked on his name I was routed to his profile. Over 73,000 hits on his profile. I clicked on my profile and I have 100 hits. Kinda puts things into perspective for me.
kevin
Thank you Fred I had forgotten about that one, how about that edge rifle from air force ? It seems like a must have too.
One winning lottery ticket please.
DB,
It's there. Perhaps you need to clear your computer's cache.
B.B.
Kevin,
Most of those hits on my profile come from the Post Office's online Most Wanted rapsheet search function. 🙂
B.B.
Kevin,
I'm with you on Crosman's attention to the marketplace and it's desires.
It's nice to see a company that pays attention! But in this highly competitive marketplace, it's a must for success!!
As for our grandmaster of guns Tom Gaylord… Well we be blessed to have him lead us through the world of guns… very, very blessed indeed!
.. and his better half, Edith, brings the package to a level unsurpassed!!
Thanks to them both…
Wayne,
Ashland Air Rifle Range
B.B.
So they're printing it out to put on their wall?
A poster boy too!!!
Wayne
Actually, the auto-safety on some of the Beeman or BAM rifles (the ones with the Rekord trigger or a copy of it) might be an exception…
The safety on those guns doesn't block the trigger – it actually disconnects the trigger from the rest of the mechanism. Or rather it prevents the mechanism from connecting with the trigger when the gun is cocked. On my B20 (and I suspect this is also possible on a real Rekord) it is possible to adjust the trigger pull weight so light as to make it a REAL hair trigger… so much so that the shock of closing the barrel or bumping the rifle will set it off. To make matters worse, the trigger weight adjuster on the B20 had a habit of backing out, so that eventually it would adjust itself to this level even if I didn't.
In a situation like this the auto-safety might actually perform a valuable function. Assuming that the shooter doesn't take it off until the shot is about to be fired. But it's probably safe to say that a trigger shouldn't be adjusted to this point to begin with, with the possible exception of competition. Still, knowing how the trigger works on these guns I don't think I mind having that auto-safety in place.
But that's the only exception I can think of…
B.B.,
Ahh, so that explains the 73,000 hits. That means I'm famous and you're infamous?
kevin
B.B.,
I'm sure you can feel the love coming from your readers. On one hand you are the friendly gun expert freely helping your fellow shooters to better themselves in the hobby. On the other hand you are the evil tempter that fuels my addictive/obsessive personality on a daily basis!
Diabolical master plan by the Owner's of PA, Thanks a lot!
Kevin,
I just hit your profile. We need to bump your numbers. I think you're up at least 10 now.
Derrick
Start teaching your 5 and 8 year old to shoot.
As much as you can teach them gun safety there are going to be times when an auto safety is a godsend!
CowBoyStar Dad
Derrick,
WOW! 790 hits on your profile. I bow to you.
kevin
B.B.,
How is the thumbhole stock on the Nitro? Does it put your trigger finger in an awkward position, or is it nicely figured?
Fused,
Good question.
The grip looks like a standard Crosman 1377 or 2240 type grip. If it is then it should fit the average person well enough.
DB
BB,
AA domes = JSB Jumbo Express?
My guess would be yes.
I never trust a safety or an air rifle in any state to be on the safe side.
Fused,
I think there some nice affordable air rifles out there. For the money, I feel the Disco, Benji 392, RWS 34 Striker and RWS 850 are some good valued air rifles. It's a good place to start, then adjust to suit your tastes and needs.
For the multi pump, I shoot a Daisy .22SG. It's the easiest pumping multipump air rifle I own. It's also 2nd most accurate and very smooth to shoot. Good for close range small game and pest hunting.
The angle on the grip on the Nitro looks in between a sport grip and a target grip. As for me and springers, I use a very light hold, so thumbhole and pistol grips are not a deal breaker for me.
Everyone,
Forums and Reviews are the best places for info…..airgun manufactures couldn't pay enough for such marketing info. Profits and margins are one thing, but having a larger market share "to boot", priceless.
Anyone catch the American Airgunner TV show? I can't get it here, unless I pay more money for a digital cable box and service. I may check into it. Will it be available on the internet anywhere?
Fused,
The thumbhole is very nicely shaped. I dislike thumbholes, as a rule, but this one is not objectionable.
B.B.
AJVenom,
That would be my guess, as well.
I don't get the channel, either , and it will cost $1,400 a year to install it.
So I haven't seen the program on television, either.
B.B.
ajvenom,
Thanks to Wayne and Vince, I now have a nice and very affordable air rifle. A RWS 94 and a 92, I'm very happy with them so far and have discovered the infamous 'hold sensitivity' of springers. I have discovered ways to hold already that it seems to like and am looking forward to squirrel season to see if I can translate them into effective hunting techniques. Learning how to hold the darn things turns out to be part of the fun. Still, I think long term I'm in the market for a Marauder because I think that part of the fun may wear off. First I may try the RWS 48/52 since it has a reputation for not being hold sensitive. Or, if the next installment of the Nitro finds it to be hold friendly it may be the one since it is lighter and with a composite stock. Never know…
B.B.
Good to hear about a nice trigger. I don't think I heard your thoughts on the Marauder trigger. Wayne said long first stage, crisp break, and three pound pull weight on his trigger. Was yours like that?
As I think about it, I would probably prefer a manual safety to an automatic one because you have to think about it. I particularly like the two manual safeties on the 1911, and I very much dislike what I've heard about the automatic safety on the Glock–released by pressing the trigger??
For the B30, the auto safety is not really a factor since my routine is so rigid that everything happens the same way all the time. I do kind of enjoy the click that it makes.
As another point in favor of magazines in guns, there is the industrial chic of loading and ejecting….
BG_Farmer, you're right that of all the considerations for a scope, the amount of light leaving an exit pupil would be about the last one, and for anything other than a highly structured competition environment it wouldn't be a factor at all. Tubb has worked things out to where he can afford to think about things like this. Speaking for myself, since I just do target shooting my concerns are magnification and image clarity. In terms of power, for anything other than a rested position, I try to balance resolution against the wobble that I get with the high powers. How do you know so much about optics?
It was 108 degrees here in California the other day. Does that mean that CO2 recovers faster between shots?
Matt61
Fused,
I can't find the RWS 92/94 on the PA listing and have not heard about these models before, but I'm glad you're happy with them. I actually enjoy experience of springers more with time and think that the pcp experience is more liable to get boring–except for the accuracy.
Looking to the future, you're a man after my own heart. I would give my strongest recommendation to the RWS 48 based on my B30 copy. You're right about the lack of hold sensitivity. The gun stays right on top of the sight picture.
For pcps, the Marauder is at the top of my list by a big margin.
Matt61
Matt!!!
Shame on you!
I wrote a whole special report ON THE MARAUDER'S TRIGGER just for YOU!
/blog/2009/6/benjamin-marauder-part-5/
B.B.
The 92 and 94 are discontinued, but Vince is still getting some refurbs which is what I got.
Fused (and others):
Concerning the hold sensitivity of the Crosman NPSS, I have to say it is very hold sensitivity. Every rifle is going to be different, including two different rifles of the same brand and make, so others might have different conclusions about the NPSS. My particular sample is extremely hold sensitive. It's more hold sensitive than my Beeman R9, which by all accounts, is one of the more hold sensitive rifles out there. I posted some info over on this webpage:
http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=18665&mid=150764#M150764
about the hold sensitivity and my way of dealing with it.
I hope this helps a little bit.
Jay
Jay,
It definitely helps RWS maybe sell another air rifle! I'll reserve decision 'til B.B. supports or contradicts your findings.
Thanks
Fused,
Is the RWS 92 built in Spain? Looks similiar to a cometa 220 and hits around 700 fps in .177. Nice for targets and small pest I'm sure. Cometa are popular in the UK. Many in the U.K. prefer them over Gamo.
I'm guessing the RWS is a Cometa M94? Perhaps 1000 fps .177.
That's a good combo, the 92 for targets and perhaps an indoor target range. The 94 would make a nice hunter.
As for hold sensativity….A springer is a springer…you get them better, but eventually dollar wise, other power plants will dominate them.
For springers and accuracy the aa tx200 mkiii and hw97 mkiii are at the top. As for hold sensativity, does anyone know what best springer around may be? Or does it always go with the most accurate springers?
AJVenom,
You have identified the correct rifles, and their purposes perfectly.
B.B.
Wow, thanks for the report. I knew you would come through for me, so I was puzzled why I hadn't seen the report. I was out-of-town on the day this was posted attending a wedding where the principals were in such a frenzy that I forgot to check back.
World-class trigger says it all, and that's good to know the super velocity spread too. Now the Marauder has opened its margin on the competition even further. With 40 shots per fill and low noise, a power adjuster gets less important.
On a different note, I was leafing through the Nancy Tompkins book and found what I took to be the key message. She claims that shooting is shooting and that the fundamentals are all the same from 10m air rifle to 1000 yard high power shooting. I was pretty sure of this, but it's nice to get it verified from the likes of her.
Matt61
Who needs the american airgunner show when you can watch cool videos like this one:
/article/The_artillery_hold_June_2009/63
Thanks Tom!!!!!
AJ
Targets of opportunity:)
I have sorta cleared an area so I can
have a clear lane to shoot up to 90 ft.
measured with a tape.I've been shooting
at my favorite reactive targets (pop
bottle tops)to learn holdover/under with
the 953 and number of pumps with the
1377 to stay on target at varying yds.
The 490 is so close that I just put the
front post at 6:oo out to halfway mark
then dead on out to max.
So I'm out havin some plinkin fun after
supper tonight,when out hops a nice
fat young bunny!He moves right up to the 60 ft. marker then just sits there
lookin across the yard!I haven't had
fried rabbit in ages.I step up to a post
to rest on and put 10 pumps in the 1377
take a careful bead and then spat,right into the marker to scare him off:)
I know I would have been the one to
clean and cook him then have to share with 4 or 5 other people when it was
done.Just not enough meat on 1 bunny
for a greedy old man and his pack,so the bunny got a pass today.:)
JTinAL
P.S I did watch where he bedded down
so if I see any more, well I still like
fried rabbit 🙂
Shhh! I'm hunting wabbit!
Cook! Cook! Whea's my Hossenpheffer!?
Sorry, couldn't resist. Thanks for the video B.B.
Seriously though,
I'm in the market for some good squirrel and rabbit recipies if you gott'em. Preparing for August 15, small game season in GA!
Fused
Usually I just fry'em up or put 'em in
a nice stew.Anything you can do with
chicken works well with rabbit.I like
to make fajita's with rabbit.Brunswick
stew is good with any small game
including dove and quail.BBQ'ed ground
hog(wood chuck/rock chuck)is great if
you marinade it for a few hrs. first.
The one tip I give everyone is to get
some ALLEGRO marinade.Specifically the
one for wild game.Much better than
worcesershire or dales sauce IMO.
Widely available in larger grocery
chains and bottled in Paris,Tn.
The regular kind is great in a roast
or for BBQ'ing.
I'll see if I've got some specific
recipes written down that I can e-mail
to ya.
JTinAL
Going with BB on this one. As soon as I cock a Beeman R or HW rifle the safety comes off without even a thought. It is pure habit.
Great video, BB.
If a picture is worth a thousand words, then a several minute video at 20 to 30 images a second is probably worth War and Peace.
Hey BB,
I have a question.
I recently rested my air rifle on some really dusty boxes and dust flew everywhere.
I have searched for some oil to cleanly wipe down the rifle.
I know you can use ballistol but I do not have some.
However I have some SAE 10 W 30 oil for the lawnmower broken. A lot of people say that you must look for ND or non detergent. But I cannot seem to find those initials. It just says SAE 10 W 30. Is that non detergent and is it safe to use it to clean the exterior of a rifle?
Thanks =)
JTinAL,
Is it only me, or does anyone else see a problem sooting small game in the summer months? When I was a boy I learned early on never to shoot edible game in warm months. The danger of tularemia is high in warm month and I believe you are not even supposed to handle small game with you bare hands in warm months.
B.B.
Oiler,
What you use on the OUTSIDE of you air rifle makes NO DIFFERENCE! Use something that prevents rust, like Sheath, Barracade or Break Free or some other good commercial preparation like that. Get it at a good gun store.
Or order it online from Pyramyd AIR.
/product/birchwood-casey-gun-and-reel-silicone-cloth?a=2703
B.B.
Interesting. Tularemia.
One of the first lessons in hunting I was given as a small boy was that you only eat small game in months that have an "r" in them. My grandfather told me this "rule" and said you'll get very sick. Since his word was law in my little world I never broke it to find out if he was right or just passing on a wives tale. Never heard of tularemia but I've learned over time that he knew what he was talking about.
kevin
I have actually heard that same rule. Forgotten it until you just reminded me.
Thanks!
My comment last night didn't read right. The first part references were for JTinAL, second part for B.B.
BB,
I am reading the on the Yellow where one person is saying "This Nitro is a Remington Genesis another BAM Quest remake copy of Hunter 440/890".
It is my understanding that the Crosman Nitro is American made. Is the Nitro completely American made, assembled in America with parts made in China, or made and assembled in China? I know you have been to the plant and know what's what.
David Enoch
David,
When I visited Crosman earlier this year I was told that the NPSS is going to be made in their factory. It wasn't yet in production when I was there, so I never saw it being made.
B.B.
David, don't believe everything you read. The Genesis is NOT a Quest rehash. It is a Benjamin Legacy 1000 rehash, and THAT gun was American made. If you compare the construction details (the endcap, the safety toggle, the trigger, the rear sight) you'll see what I mean.
The Legacy 1000 follows the general breakbarrel formula and therefore has some similarities to the Quest. But it is not a copy or clone, and is not patterned after it.
The behavior of the rifles is quite different as well. The Legacy has a larger bore (28.5mm vs. 25mm) and a shorter stroke (83 vs. 100mm) to give about 6% more powerplant volume. The Legacy also has a very heavy top-hat, giving it more of a 'kick' when fired.
The construction of the Legacy 1000 is certainly superior to the Quest when it comes to things like the fit and finish of internal parts. But I'm not so sure the design is any better.
I owned a Genesis 1000 before it was discontinued about a year ago. It shot okay but was very very hold sensitive… maybe I needed a wider pellet selection.
After two weeks the barrel became loose, the breech block failed and no longer held the barrel in place. It could rotate and wobble when clocked.
I returned the gun for a refund…. I certainly hope this Nitro avoids the same quality issues.
BTW. Why was the Genesis 1000 discontinued? Quality? Lack of Sales? Ramping up for the Nitro?
Hey, just wondering if you have tried the Gamo Silent Cat? I went to the store all set to buy a Whisper, but when I got there, they had a "Silent Cat" with the same sound dampener as the Whisper, but with the scope and power of the VH. Just wondering if anyone has actually tried the Silent Cat yet, I searched around online and not even the Gamo website has it listed, must be something new, a hybrid of the VH and whisper?
The Silent Cat is available on Pyramyd Air's site.
It IS a new gun this year and is the same gun as the
Big Cat but with a different
stock (same stock as you'd find on the
Whisper VH combo).
Edith
Ahh, yep from reading up on the Big Cat that sounds like it. Looks like a combo of Big Cat meets Whisper VH. I picked one up, took it out sighting a bit, was doing nice 1 inch clusters with Gamo Match, spread loosened up a lot as i changed to Magnum and PBA, so guess each ammo will be slightly different with this one, pretty sensitive.
can some body help me with this. you tested the velocity with a .22 cal rifle, when you got those numbers was the gun broken in yet or no? please email me with the response, thanks. ybin90@gmail.com
Bin,
Normally B.B. (Tom Gaylord) is loaned an "off the rack" gun for testing. The first shots on the loaned gun are by B.B. I don't know for a fact that the Crosman's new Nitro Piston Short Stroke was off the rack but the odds are that it was. Therefore, in answer to your question, it's very likely that the gun was not broken in.
kevin
Bin,
Kevin is right, but I will say this in addition. In my experience, a gas spring gun doesn't require the same break-in that a steel spring gun does. So those velocities will be very close to that all the time.
B.B.
how much energy will you loose in a .177 npss, instead of 16.1 foot-pounds with crosmans how much will it drop.
Huh?
B.B.
the gun you tested was a .22 would the muzzle energy be the same in .177
A .177 will generally lose about 20 percent of the muzzle energy of the same gun in .22 caliber. There are exceptions to this rule, some guns lose a lot when they go up to .22 caliber, like the Gamo CF-X and the Whisper.
But 20 percent is the general rule.
Also, in a spring gun you want to shoot the lighter pellets, so in .177 you want to shoot 7.9-grain Premiers–not 10.5 grains.
B.B.
PART ONE
(please forgive -it's a complicated comment)
I know this post was created a several months ago, but the subject matter seems most pertinent to my inquiry.
First, I am very grateful to the research and information made available by Mr. Gaylord, Pyramid Air, and visitors of this blog. My air gun experience is enriched by this valuable resource.
I just recently acquired a Crossman NPSS .22 after much research on the internet. The reason for this comment, is the possible difference in the NPSS FPS/FPE and frequency of chamber lubing.
I have run across several posts such as this one on the NPSS. Many record various pellets and their respective FPS data. It seems that others have recorded data using medium weight pellets very similar to Mr. Gaylord’s. Similar data, ultimately puts the NPSS solidly in the 15 foot-pound energy range. Yet, many other postings by different individuals, show various pellets recording slightly higher velocities in the mid 700 FPS range with the NPSS. It should be noted, all seem to show that the 14.3 grain Crossman premier with very similar results in velocity. This is usually credited to pellet and barrel size issues.
The 50 FPS higher (on average) velocities recorded by others, doesn’t seem significant, but ultimately puts the NPSS in the 17 to 20 foot-pound range.
Revisit chamber lubrication and the combustion phase of all spring piston air guns.
According to a past post on this blog by Mr. Gaylord Titled, “Lubricating Your Spring Gun: Part 1-chambers & mainsprings”-
The following guidelines for spring guns were given:
For guns with synthetic piston seals use a silicone lube with a high flashpoint. Use VERY LITTLE – perhaps one drop every 1,000 to 3,000 shots.
For guns with leather piston seals, use silicone chamber lube in greater quantities, because it's constantly being wicked away and drying out. Perhaps, five drops every 500 shots is about right.
The Owners Manual for the NPSS states, “to insure that your air rifle maintains uniform power, it is important that you apply a drop of RMCOIL every few hundred shots into the compression chamber”
Continued in PART TWO
PART TWO
This flies in the face of chamber lubrication and modern piston seals. Yet, it is in the owners manual for the NPSS and I can only believe that Crossman has it in there for a good reason. Also, few is a rather ambiguous term. If a couple means two, and the term several was not used, I can only guess that “few” as used in the NPSS Manual means three to four hundred shots.
According to a very informative past post in this blog titled, “Do All Spring-Piston Air guns Diesel?”, it was stated that spring-piston air guns in the NPSS power range produce their power through the combustion of chamber oil.
The combustion phase
“piston compresses the air, the heat it generates is so high that it ignites any small droplets of lubricants that may be present in the compression chamber. What the Cardews proved by their testing is that all powerful spring-piston guns burn fuel to generate their power.”
The post also states that detonation occurs with an abundance of fuel in the compression chamber. The NPSS manual cautions the operator not to over-oil.
Given this information, I am interested in the chamber oiling habits used by operators of the NPSS while recording the data of FPS and subsequent FPE of various pellets and their respective weights.
I can only theorize, that those showing pellet velocities in the high 600’s to low 700’s with the NPSS, are lacking the proper amount of fuel in the compression chamber for optimum combustion and therefore power, because they are not adding one drop of Crossman silicon chamber oil to the compression chamber every “few hundred shots”.
AND those realizing FPS in the mid 700’s with medium weight pellets, are lubricating the compression chamber as prescribed in the NPSS manual.
The difference is about 3 foot pounds of energy. This is a significant amount. Especially when choosing the means to humanely dispatch pests.
Without a Chrony of my own to conduct an experiment. I am wondering if anyone who has compiled FPE data with the NPSS would care to share their use of chamber oil per hundred or thousand shots? Any other thoughts on the matter would be greatly appreciated. Thank you.
Respectfully submitted
TM
TM,
You raise an important question:
"Are the instructions found in airgun owners' manuals to be believed?"
The answer is sometimes yes and other times no. Some manuals are made by cutting and pasting other manuals. The people writing them haven't a clue what's right and there is nobody who is knowledgeable to review them.
But every once in awhile there is an important fact put into a manual.
If you own an NPSS I would follow the Crosman guidance until it is proven wrong. Then you have the company behind you. But if your gun starts detonating (exploding) all the time, STOP lubing it!
B.B.