Big Cat Pellet Test Accuracy Report

[hdrider]

I picked up an assortment of pellets from Pyramid Air and decided to try to find the most accurate for my BC.  The BC is stock except for a GRTII Trigger and the addition of a CenterPoint 4x16 40mm AO Scope.  The gun has several hundred and perhaps over 1,000 rounds through it, so it should be broken in.  I was never impressed with the accuracy, so I thought I'd search for a pellet it likes.  All testing was at 15 yards and the results are the average and standard deviation of 5 groups of 5 shots each.


Crossman Premier Domed 7.9gr
.614" Avg, 0.263" SD
Crossman Premier Pointed Hunting
0.943 Avg, 0.224 SD
Crossman Destroyer
0.771 Avg, 0.168 SD
Crossman Premier Ultra Magnum 10.5gr
0.907 Avg, 0.371 SD
RWS Superdome 8.3gr
0.584 Avg, 0.152 SD
Predator PolyMag 8gr
0.531 Avg, 0.177 SD
JSB Exact Diabolo 0.547g (8.4gr)
-.662 Avg, 0.226 SD
JSB Exact Diabolo 0.670g (10.2gr)
0.379 Avg, 0.233 SD
Beeman Field Target
0.517 Avg, 0.064 SD
Beeman Crw Magnum
0.642 Avg, 0.243 SD
Beeman Kodiak
0.580 Avg, 0.176 SD

The results showed the Heavy JSB Diabolo to have the smallest average group size (due to one very small group), but only so-so cosistency.  The Beeman Field Target showed the best consistency  and resonably small group size.  If I had to choose I'd pick the Beeman Field Target baed on this set of data.

However, believing that I should be able to improve both Accuracy and Consistency, I've sent my BC to Pryamid Air to get a Gas Spring installed.  I'll repeat and repost the results when I get the gun back.

Any Comments -- especially those that have a Big Cat and/or Gas Spring Conversion?

[larspawn]

hdrider,

You didn't try my Big Cat's favorite pellet...Crosman Premier Hollow Point (Walmart!).  

TX CPLs  on the left, Big Cat on Right.  From bench at 25 yards.

[hdrider]

larspawn,

Your BC accuracy looks a lot better than mine.  I may have some CPHP kicking around somewhere -- seems that they generally shot about the same as the CPL's (domed 7.9gr), but it may be worth another look.  What modifications have you done to your BC -- trigger, scope, tune?  It could just be you're a lot more proficient at shooting a springer -- this is my first and only one.  From your sig it looks like you've got a lot of experience with them.

[larspawn]

hdrider,

Yes, as stock the BC was horrific.  I changed out the terrible trigger with a GRT (I hear the new triggers are better) and a tune with a JM 3650 spring and Apex seal.  Much better.  I hear the gas rams can be scope destroyers so make sure you put a good scope on it.  I've mounted a cheapy 6-24x50 Tasco ($55) which has held up great.  I must say that for the price the BC really is a great shooter.  And those were 5 shot groups!

Andy

[Furseeker]

Maybe I got lucky and got a good one, but my Big Cat is a real tack driver. It still has the stock trigger and I'm thinking about replacing it this winter. The spring and seal are new, probably less then 100 shots on it. Mine likes the CPHP and Crow Mags, I never know where the PBA is going to end up so I gave up shooting them. Let me know how the gas spring swap goes. I was thinking about doing that but I'm hearing alot about how hard on scopes they are.

[larspawn]

Which spring did you use?  I used a E3650 and apex.  I just put a Tarantula in a Quest which is basically the same action.  Woa is there a difference.  The BC with E3650 and Apex is shooting CPHP at 830ish.  The Quest with the Tarantula and stock seal is shooting CPHP at 1150 fps.  Not sure but I hope this calms down.  Way too fast!

Andy

[triry]

i cant complain about the big cat,...my son ryan ( 11 years old ) shot this group the past weekend............

http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=22330&mid=177509#M177509

[Furseeker]

I used the Tarantula sprind with and Apex seal. The stock spring was bent and had a pretty good twang. Now it has a solid sounding thud. It's not as quite as some wood stocked guns. Right now it's on loan to my brother, doing some pest control work on magpie's. But I think this weekend I will get it back and try to feel the stock with spray foam insulation to see if that will at least deaden the sound by eating up some vibrations. What do you guys think, will that help a little. I've heard alot good about the after market triggers for this gun. Maybe I'll add that too. I saw one on this site somewhere with a pretty tricked out camo stock. That was a good looking gun. Now I want to put a new power plant in my Beeman RS2. Any suggestions out there?

[Furseeker]

Wow, i just read that again. 1150 fps is mega fast. What kind of groups can you hold with that kind of speed? I like speed but it has to be accurate or I just miss fast. Let me know whrere it settles in at please.

Thanks
             D. Rendon
             aka furseeker

[hdrider]

I got a call from the Tech at PyramidAir about the Gas Piston conversion for my BC.  They received my BC and immediately noticed that the barrel was bent to the left -- said that it was apparently defective from the factory.  I told them it shot way left out of the box, but I hadn't noticed it was a defective gun -- guess I didn't know any better.  The gun is less than 6mo old so it's still covered by warranty, but i already paid to ship it to PyramidAir -- I asked PyramidAir if they could deal with GAMO on the warranty since they already had the gun.  The tech said he would check with another expert about the barrel misalignment and if it could be fixed there, or barring that if the sales dept could work something out with GAMO on a warranty replacement.  I guess in the best case PyramidAir will take care of this and in the worst case I'll get stuck paying for shipping to and from PyramidAir as well as shipping to GAMO for warranty replacement.  Needless to say the Gas Piston conversion is on hold for awhile until I can get this mess straightened out.

LATEST INFO -- I just got off the phone with the PyramydAir Tech.  They asked me to e-mail a copy of my purchase receipt to them (which I did a few minutes ago) and that they would talk to their sales department to see if they could work with GAMO to get it replaced under Warranty.  Hopefully the sales department at PyramydAir will be as understanding as the Tech Department has been.  I'll post the status when I get another update from PyramydAir.

[larspawn]

furseeker,

Have you chronied your BC with the Tarantula?  I put the E3650 in and lost about40 fps.  Now shooting around 830ish with CPHPs.  But I put a Tarantula in a Quest this weekend and it is shooting CPHPs at 1150 fps!  I can't believe it.  Just wondering if you were getting extreme fpe with th Tarantula.  

Andy

[hdrider]

Looks like my thread has been a bit hijacked.

Anyway,  everything turned out good with my Big Cat and Pryamid Air.  They were able to replace the gun I sent them under the GAMO warranty and put a Gas Spring in the new Big Cat they returned to me.  Initial impressions of the gas spring are it's pretty awesome.  It takes a bit more effort to cock, but it's  very smooth and feels like it's shooting pellets faster.  Only had a chance to fire a few Crossman Premier Lights to sight the scope in, but looks like this is going to be a real accurate gun that's easy to shoot (less hold sensitive).  This coming week I should be able to do pellet accuracy tests at 15 yds and perhaps chrony some pellet velocities.  Since I've got a variety of Pellets to choose from (see the first post), which type/weight would be the most useful to chrony for the other forum members here?

[hdrider]

I decided to start a new thread to specifically discuss the Gas Spring and Velocity and accuracy results -- this is my last post on this thread.