Big Cat 1200 Tune

[gatonini]

Yesterday I tuned my big cat Apex seal and E3650 spring from JM dont know If I screwed up or what I stood a piece of 3/4 pine in my backyard and shot
at it with two different pellets Crosman HP premeires and Crosman pointed. The pellets would only penetrate about the lenght of themselves in other words
the skirt was flush with the face of the board. Does this sound right or do you feel I screwed up the seal on the piston?

                                     
                                                    Thanks for reading
                                                     Gary

[redroush00]

What distance? My big cat will burrow more than a half inchinto a 2x4 at point blank and well past the skirt at 13 yards.

[Bogey]

What distance are you shooting?  Also,  it may depend on what type of wood your are shooting.  If a hardwood, that may as good as it gets.  If a softwood like pine it should pass through.   I just finished replacing a piston seal on a BC yesterday and the AG is shooting harder now than when new.    However,  I had to try several seals to find one that fit the compression chamber the best.   Also, even though the gun has been de-burred,  I carefully work the seal past the slots cut in the tube to avoid any possible damage to the seal.
After assembly, I flattened a soup can and taped it to a one gallon milk jug filled with water with another guart sized container behind that.  At 45 ft, a CPHP  passed through the flattened  can, the milk jug, and the quart behind .  Pellet found imbedded in the back stop.   Before the water drained out,  I shot several more times with the same results.

And it may not be just the seal.  Could have some spring issues too.

[LongIslandArcher]

Yeah, something doesn't sound right.  Your pellets should be passing right through the pine.  My CPHP pellets embed themselves 1/4" into 3/4" plywood from 65 yards (in .22 cal.) with my Crosman NPSS.  

Did you deburr the receiver tube before you pushed the piston and new seal into the compression chamber?  If not, chances are you gouged the seal.  Are you sure the JM E3650 spring is the same power as the stock spring?

[CharlieDaTuna]

I really doubt that the pellet will "pass" through 3/4 inch pine. Like I stated in the e-mail, unless you crony it, it will be difficult to determine what it is actually doing. Even though it's pine, wood has different density and from one board to the next, it can be different. Also, the E-3650 is a little softer but much more docile spring with a whole lot better firing cycle but usually shoots about 20 fps slower. Well worth the trade off.

LongIslandArcher has a very difficult time comparing apple to apples and much of his info and comments are not quite accurate and can be misleading.

[LongIslandArcher]

Bob, I put pellets through 3/4" pine with my NPSS in .22 cal.

If he's shooting .177 at a close distance, they should be going through also.  Tomorrow, I'll shoot my .177 CFX at a pine board and I'll take pictures of it.  How's that for comparing apples to apples, since both rifles are rated at 1000 fps with lead?

[LongIslandArcher]

Wait a minute, I shot at 3/4" plywood at 10 yard with my .177 CFX while at Cobra airguns and the pellets went through, and I have witnesses.  And it was wet plywood too, so not only was the wood swollen, but it's made denser by the water.

[djmyers]

I shoot a 2x6 and the daisy pellets did the same thing. You couldent rub your hand over it with out catching but the JSB and HN pellets went about 3/4 in in. And all the other ones buried in at least twice the pellet length.

[pgsmith]

If you don't have a crony try shooting a telephone book, with CPHP's and my Big Cat completely stock I am going 570 pages into the book. Now to better describe the book there are none of the heavy pages after the cover it goes right into the thin phone book pages and I am counting up to the last page of tear.

I am only propping the book up not taping or tying it to anything but leaning it against my target box.

[LongIslandArcher]

I can tell you then that when I shot my .177 cal. CFX with an air venturi gas ram, into a phone book using Crosman Copperhead pointed pellets, the pellets went in about 925 pages.

[shadow]

Got to have a chrony when checking the health of a shooter. Ed

[crackshot777]

when i first got my big cat it was punching through 1x6 at 15 or 20 yrds i cant  rememberi know i was really impressed with it.

[pgsmith]

I haven't tried the pointed pellets. Hmm I think I should. BTW I bought my wife a Ruger Air Hawk Elite and with the CPHP's it went 718 pages into the book, I was impressed I only paid a little over $100 for the rifle.

[crackshot777]

i forgot to mention that i was shootin crosman pointed and not crosman hollow points

[speedturtle]

Don't take guesses, do yourself a favor - buy a Chrony and take a reading. One of the issues with changing parts are tolerances in size and with the small apex seal it might be too tight on your compression tube. I know because it happened to me. CDT is right that the E3650 spring will give you less FPS but with a faster shot cycle. If you are into higher velocity then you can simply use the original stock spring and you'd be amazed that it shoots faster. The only negative point about it is that it is not as strong as any JM springs that you can use. My E3650 spring has more than 15,000 pellets now and still giving me consistent FPS with an extreme spread of about 17 FPS. The stock spring broke on me at only about 1,500 pellets. Good luck if you can buy a replacement spring from Gamo.

ST