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yourdaddyjoe · Supporting Member

Okay... so I figured since I will be wacking Whistle Pigs from Feb-June... I needed a bench gun worthy of 100+ yard kills and not move one bit for follow up shots... So Bench b!tch got some new mods...

Went ahead and put one of my PBG Stock adapters and another Carr stock with cheek rest on it...

It may be a bit of over kill... but what the hay... I machined up a BMG style Muzzle Brake for my 16" Threaded Bull Barrel... It does the trick to keep it still...

I also reworked the valve and added a heavier hammer spring...

I let you know how it does... Camping this weekend... Mr. Green

rsterne · Moderator

Nice setup, Joe.... What are you getting out of her?.... JSB 18 gr. Heavies I presume?....

Bob

packrat · Senior Member

Nice looking set-up there Joe.....I'm curious but afraid to ask what the "L"
"wacking Whistle Pigs" means so..................I'll let it go-

yourdaddyjoe · Supporting Member

Only one drawback of where I live now... Can't shoot it in the back yard... Sad/Cry

Going to take it with me camping... I will get #'s there...

yourdaddyjoe · Supporting Member

Mark5043 · Silver Status Member

sniper · Silver Status Member

i thought it was the disco. Rolling Eyes

what is it based on again? Rolling Eyes

broommaster2000 · Moderator

It should be magazine fed. Razz

Nice job, the Break gives it just that little extra. Wink

kanyon · Silver Status Member

Joe....
We need better pics of the qute little muzzle break...

Looks dam nice....

Pete

scroller99 · Veteran Member

muzzle break would look at home on a 50 cal. Twisted Evil

yourdaddyjoe · Supporting Member

First blood with it yesterday and all day today... Lots of little pigs in the 100 yard range from the bench, no sweat...

I have it dialed in at 980 fps with the .22 JSB 18.1 Hevies... Teatherd to a SCUBA tank with a 1800 psi Reg. in line...

Barring wind changes... I can take a whistle pigs in one shot... over and over again... Who needs to put groups on paper??? Moving targets are more fun...

One little change coming up... I am going to have to go .25 Cal... Twisted Evil

My attempts for 2 for 1 pig shots are "No Bueno"....

rsterne · Moderator

SWEET.... 38+ FPE from a 22XX based gun.... I got 37 FPE on 1600 psi and 41 FPE on 1900 (both with JSB 18 gr. Heavies) so we're on a par.... Mr. Green

I've been doing the numbers on wind drift with the 18 gr. Heavies.... I think 900 fps MV is about the optimum.... The BC is pretty consistent at 0.036 - 0.038 from 650 - 850 fps.... then it takes a dive.... At 900 fps it 's down to about 0.030 and at 1000 fps it's down to about 0.020.... Shocked

Here are some measured numbers with the JSB 18 gr. Heavies:
1000 fps MV gives ~ 870 @ 25 yards (130 fps loss)
900 fps MV gives ~ 815 @ 25 yards (85 fps loss)
820 fps MV gives ~ 755 @ 25 yards (65 fps loss)

Since wind drift is proportional to the difference in flight time in the real world and in a vacuum.... there is an optimum MV to minimize drift.... I'm going to set up my 2260 PCP Bench Rest Rifle for 900 fps (32+ FPE) with the 18 gr. Heavies for that reason.... Wink

BTW, I just put in a 100 yd. range at our Placer Camp c/w Bench....

Bob

Mark5043 · Silver Status Member

Nice!...980 FPS is cruisin..Just wondering.. is it possible to hit those figures with a heaver .25 pellet???

yourdaddyjoe · Supporting Member

rsterne · Moderator

I converted my modded Disco to .25 cal..... It went from 53 FPE max in .22 cal to 58 FPE max in .25 cal.... no other changes....

.22 cal:
JSB 18 gr. Heavies at 1080 fps (46.6 FPE)
H&N 21 gr. Baracudas at 1030 fps (49.5 FPE)
EunJin 28.4 gr. Domes at 909 fps (52.7 FPE)

.25 cal:
JSB 25.3 gr. Exact Kings at 975 fps (53.4 FPE)
H&N 30.9 gr. Baracudas at 919 fps (57.9 FPE)

So basically, with similar pellets, you lose about 100 fps in .25 cal.... but gain in energy.... The numbers above were the highest I recorded, not averages.... Mr. Green

Bob