gas gun practical use 260 vs. 6.5 creed vs .308

[toddconley]

What kind of velocity can I get from a gas gun in 260 with 123s. Vs 6.5 creed with same bullett vs 308 with 155 scenars. I have tons and tons of 308 brass. I am looking for a match gun. I am keeping barrel to no longer than 18in. I'll do the math on drops and so forth but I need to know how fast they will go. Could a few people help me out?
Thanks,
T

 

[ponchair]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

I got 2750 fps out of my 18" .308 Noveske. Accurate to 1000, even at -2500 DA.

46 grs Varget, Win Brass, BR-2 primers, with 10 oz buffer, Tubb spring, and Tubb CWS.

 

[toddconley]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

Is that with 155s?

 

[BCP]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: toddconley</div><div class="ubbcode-body">Is that with 155s? </div></div>

I wouldn't plan on getting that sort of velocity out of an 18. You might get it or you might get one like mine that is hard pressed to go past 2650 with 155's.

 

[ponchair]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

Correct, 155's.

 

[Unknown]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

What kind of 155 grain bullets are you using? The heaviest bullets I could find that have a decent BC (.615) are the 144 grain Lapua. A 155 with decent BC (.635?) would be really neat. I would really like to find out more about the 155 grain 6.5mm bullets.

I know that there are some 160 bullets, but they are round nose for game, not targets.

 

[ponchair]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

Lapua Scenars

 

[toddconley]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

What bc are you thinking for the 155s? Did he say 144s with a 615 bc? Not aware of those?
school me
t

 

[BCP]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

155 palma style bullets should have a BC of .5ish at 2850 or so FPS.

Maybe you should say what kind of matches you want to do & how much you want to spend?

And why 18"? Do you want to carry it around etc or just for looks?

edit: 140-144 grain 6.5 bullets are probably what he means, as far as I know all of those are to long to be mag fed. The 123 amax is probably your best bet for that sort of bullet mag fed.

 

[vmpglenn]

Re: gas gun practical use 260 vs. 6.5 creed vs .308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BCP</div><div class="ubbcode-body">155 palma style bullets should have a BC of .5ish at 2850 or so FPS.

Maybe you should say what kind of matches you want to do & how much you want to spend?

And why 18"? Do you want to carry it around etc or just for looks?

edit: 140-144 grain 6.5 bullets are probably what he means, as far as I know all of those are to long to be mag fed. The 123 amax is probably your best bet for that sort of bullet mag fed. </div></div>

Given a 2.820" COAL for .260Rem or 6.5 Creedmoor, both the 140gr Amax and the 140gr Berger VLD (not the long range BT) will work just fine. IIRC 2.820" is the COAL for M118LR and is the max COAL to be able to use the Magpul LR20 magazines. the KAC and LaRue .308 mags are a little more generous.

ETA: The Berger 140gr VLD has a G7 BC of .313, G1 of .612 (Bryan Litz's numbers).