Detuning The Silent Cat

[avator]

Welp.... soft bedding ain't gonna work.. just had the stock off and the action in the FireCat sits on a series of 1/8" ribs spaced about 1 1/4" apart down both side of the stock. Nothing solid to put bedding on. No biggie, the tune really has the twang tamed to a nice solid thunk.

[avator]

No Wonder !!!
Sun popped out for a minute so I thought I would run a string across the chrony to post. First shot 430.. huh? second shot.. bout the same... WTH? Down to the shop we went. Opened her up and noticed.. where did that 3/4 inch preload go? pushed the pin out and took the spring out.... oh there it is... 2 coils snapped off and twisted inside themselves on the tophat. That was lucky. No damage. LMBO that explains why the shot cycle smoothed out and the cocking effort got nice and easy. So I thought, ok, I'm just going to put the full spring back in and see how hard it cocks and shoots. Back up to the chrony and the string went low 609 and high 623. That's where it was when I first cut the spring.. Something ain't right here... went to the shop to see if I grabbed the wrong spring and there it was... I forgot to put the tophat back on... and what's that? Oh dang, I forgot to put the safety linkage back in as well.. No big hurry to put the tophat in, it shoots very well but I absolutely need to put that safety in. I got time to take about a 2 hour nap before work tonight so FireCat is resting in it's case until tomorrow morning.

[longhunter]

Welp.... soft bedding ain't gonna work.. just had the stock off and the action in the FireCat sits on a series of 1/8" ribs spaced about 1 1/4" apart down both side of the stock. Nothing solid to put bedding on. No biggie, the tune really has the twang tamed to a nice solid thunk.

the dusk had the same setup. I just ran a length of the adhesive foam across the top of all of them, kind of like a suspension bridge. the back half was easier to do. at least on the dusk, it was solid. you can always put the foam on the comp tube. that way, you can guarantee you're gonna make contact with something.

[avator]

There ya go... I'll put it on the tube.... Dang Scott, you ain't as dumb as I look! Thanks Bud.

[avator]

BTW... Did it create any slop in the linkage? You know.. that little roller guide rides on the plastic ledge....

[avator]

Bedding came UPS today so I replaced my makeshift job with the real deal. I tarred the snot out of the original spring (it has a couple wiggles in it but I've seen much worse). I left the tophat out but moly lubed up a good old copper penny and dropped it down the rabbit hole. Did a bit of spring squeezing, polishing and moly in the trigger group and slapped it all back together. The trigger ain't no CDT but it's better. This thing now has a real nice solid thunk. I'll chrony it again to see where I'm at but, I'm liking it alot. It is now putting 10.5 CPUM in a dime at 25 yds as many times as I can pull the trigger as long as .... well, you know. The bipod kit will be here Saturday then it's on to the next one. I'll put the final pics, stats and groups up when it's done. It turned out much more than I expected. I can see alot of enjoyment coming from this.

[stonykill]

perfect

[shadow]

Been watching this post closely very interesting. Looks like your on to something bud and looks good. I've tuned countless Gamo's and no stock stuffing etc. beat's a good tune to tame the beast. Rubber does have great dampening qualities and I use it in my hollow stocks as well as in the ribs inside the stock. Ed

[avator]

Thanks guys... I ain't no engineer but, with this 6" barrel, you pull the trigger and the pellet is gone before the gun really even knows what's happening. I know it don't take long for a pellet to zoom down a full length barrel but, our bodies react pretty darn quick without us even knowing it. I can't help but wonder if the pellet is not already gone when I react to the recoil because this thing is so easy to shoot. I highly recommend anyone who likes to tinker and make neat stuff, grab one of these (or one of it's many equals) and chop it up. I've done a number of 13XX and 22XX carbines, HPA stuff, camo painting and stock carvings but, this is by far the funnest, most rewarding one yet and I really didn't do a whole lot. Just a ton of fun on the cheap.

[stonykill]

Been watching this post closely very interesting. Looks like your on to something bud and looks good. I've tuned countless Gamo's and no stock stuffing etc. beat's a good tune to tame the beast. Rubber does have great dampening qualities and I use it in my hollow stocks as well as in the ribs inside the stock. Ed

 Rubber... so will EPDM pond liner, rv roofing material work? I have a bunch of scraps of that laying around. And will it also work in a wood stock? Or is that just best for plastic?

  And Ed, you use the rubber just for sound dampening? Or as bedding. Thanks!

[stonykill]

 Trust me Bill, that is on my too do list. Once the right deal on a donor AG comes. I love carbines, and honestly, I never thought of building a carbine springer. What a great nutter gun .

[OleTomCat]

Been watching this post closely very interesting. Looks like your on to something bud and looks good. I've tuned countless Gamo's and no stock stuffing etc. beat's a good tune to tame the beast. Rubber does have great dampening qualities and I use it in my hollow stocks as well as in the ribs inside the stock. Ed

Ed,

Glad to see you back on the forum, hope you are doing well.

Al

[avator]

One of the downsides to my current 2nd shift desk job situation is alot of "think" time. I'm beginning to wonder if I havn't created a major spring killer. Not alot of back pressure with that 6" barrel. Makes me wonder how close to "dry fire" each shot is. I did pack the heavy tar on it. More than I've ever used on a spring. I guess time will tell.

[longhunter]

BTW... Did it create any slop in the linkage? You know.. that little roller guide rides on the plastic ledge....

none that I could notice.

[shadow]

I'm mucho better these days Al thanks. Stonykill I actually had some 1/2 inch rubber mudflap material on hand and cut to fit in the ribs. As for the hollow cheek rise area of the stock I found rubber similar to pond liner and stuffed the back of the stock tight. The use of heavy tar is ok in a tune but too much will end up migrating off the spring and find it's way everywhere. The spider web effect is what you want to see on the spring. I would monitor the springs health if you think the lack of back pressure will result in possible piston slam and spring damage. Custom fabbing airguns is a trial and error thing at times and done plenty of that but that's part of the enjoyment of working on em. Ed

[Sfttailrdr46]

Another off the wall Idea use a heavyier pellet to slow down the launch time a ms or so

[avator]

lilysdad actually hit on the solution IMO. If it starts breaking springs I'll just start snipping coils until I find that sweet spot.. If it turns out that it drops below 8 fpe before it stops breaking them I'll look for another barrel and  chop it longer. Or put it out at the end of the driveway on Monday morning.... 

[stonykill]

 Longer barrel is how I would do it. Longer barrel, no "thing" on the end. And yeah, I think Gabe is correct.

[avator]

WOOHOO !!! USPS just showed up with the Bipod... problem.... I must have read the deal wrong... they didn't come with the picatinny rails.. no biggie there is a outdoor store just down the road.. gonna run down and grab some now.

[avator]

COOL !!  The FireCat is finished !! Toss it on the "done" pile and lets move on to the next one.
I decided not to remove and fill in the holes for the front and rear sight. I would rather find a set so it can be stripped down and shot with open sights.
What ya'll think?