Range Report Going from 26" to 20" 308... ?

[TannerGun]

A 700 Police I've got here is running the 178gr HPBT (Hornie) very nicely, but I'm just not that fond of the 26" tube.

I'm running 45.5gr Rl-15 (yes, this is more than most guys are using I think, but the throat in this rig is a mile deep), and seeing 2720fps at 7300'.

Can I expect to still be at around 2600fps with this load if I give it the old chop?

 

[jamesZ71]

Re: Going from 26" to 20" 308... ?

pushing the 178 amax @2607fps-2641fps out of my 20in savage
with
44gr of varget
CCI primers
Federal Brass

 

[roggom]

Re: Going from 26" to 20" 308... ?

Getting the same as james 178 Amax and match 44.4 Varget/lapua/wlr in an SPS-Tac 1:12 20", low to mid 2600's @ 4585 feet.

 

[TannerGun]

Re: Going from 26" to 20" 308... ?

Good stuff. I figured 100fps for that 6" of barrel was a good guess.

 

[MontanaMarine]

Re: Going from 26" to 20" 308... ?

I cut one from 26" to 20.5" (22" with brake), and lost about 90 fps.

 

[TannerGun]

Re: Going from 26" to 20" 308... ?

Cool, thanks Shane. I'm wanting to play around with the 178 HPBTs at mag length and see how they shoot. I've got them out at 2.96" and they're still jumping, although I don't know how far. Don't really care too much...

I guess no matter how much velocity I drop I'll still be able to dial it back... old velocity whore habits die hard.

 

[MontanaMarine]

Re: Going from 26" to 20" 308... ?

They will most likely shoot fine at mag length. I've had good accuracy with the 155 Scenar, 168 Nosler, and 178 AMax at mag length, and they were all jumping nearly 1/4" to the lands.

 

[TannerGun]

Re: Going from 26" to 20" 308... ?

I'm really anxious to try that out. I don't mind single feeding, but it's nice to be able to feed from the mag when I want to do some exercises and speed work and stuff like that. I'll probably have to knock that load down a grain or 2 first though.

 

[Bruiser_Joe]

Re: Going from 26" to 20" 308... ?

i absolutely cannot stand long barrel 308's. 20"-22" is the longest i'll do. 18" will get you pretty much as far as you want with a 308.

i have hit 60 percent IPSC targets at 1200 consistantly with a 20" 308 bolt and 20" GAP10

short barrels for the win

 

[TannerGun]

Re: Going from 26" to 20" 308... ?

BigJoe, how about some more info? Bullets/loads/speeds, etc? You've got my attention

 

[opshin556]

Re: Going from 26" to 20" 308... ?

I have contemplated this very issue often. I run a 26" 700 .308
USO 3.2x17, and feel the size and weight of the rifle are more akin to a .300 WM.
Chopping the barrel to 20" would make the rifle handier, increase the hit probability if forced to deploy from an offhand position.
The .308 is plenty for most barrier penetration in urban areas and can reach out a beanfield or two in the country when required.
Anyone know of any good gunsmiths in the So Cal area that perform this work, im interested.

Post the results, in interested.

 

[Bruiser_Joe]

Re: Going from 26" to 20" 308... ?

m118 straight up suplus ammo nothing special. it does not take much.

there is video of frank (lowlight) hitting 1000 meter targets with a gap gladius on here. you do not need a 30" barrel 308. most of the powder is long since burned at 20"

 

[TannerGun]

Re: Going from 26" to 20" 308... ?

I've seen that video of Frank with the 18" (I believe) Gladius. That's crazy impressive, now if I could just shoot like that

Thanks! Looks like I'll give my smith a shout.

 

[Mattrmvpd]

Re: Going from 26" to 20" 308... ?

I have an 18" PSS (308) that is threaded and has a Vortex on it... Only REAL difference is a little more of a push on recoil.

There really is NOT much difference in doping it out... there is a tad of change at longer distance... but 100-400 is pretty much the same...

Mine ONLY eats 175 Match... and is actually a very impressive rifle to have the factory tube on it. Trigger and Bolt have been worked but other than that it sits in a factory stock.

The BIG advantage is that it is extremely handi and is much easier to move around.

Matt (LEO SOUTH GA.)

 

[TannerGun]

Re: Going from 26" to 20" 308... ?

I've got 1500 178 BTHPs coming to me so it will chew on those for about a year or however long they last me. If I chop, it'll be to 21", I do believe.

 

[Niles Coyote]

Re: Going from 26" to 20" 308... ?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MontanaMarine</div><div class="ubbcode-body">I cut one from 26" to 20.5" (22" with brake), and lost about 90 fps. </div></div>

This/\

A little over a year ago I tested two different loads in my 26" varmint and 20" tactical both remington factory rifles in 308. One load with the 155 scenar and the other with 175 smk. The velocity difference was 100fps for the 155 & 90fps for the 175. I was using Winchester brass and primer along with varget for fuel.

FWIW 2.825" works well in both of these rifles with every match king I have tried (168, 175, 180) and the 168 a-max. Berger 168 vlds like to be ~2.810-2.815"

 

[Bob 964]

Re: Going from 26" to 20" 308... ?

I would think cutting a 26" barrel down to 20" will cost you 100-150 FPS in velocity. The trade-off should be improved accuracy. A 20" barrel will be stiffer and the harmonic effects should be less. If the barrel is flexing less, it should be easier to hit your target.

 

[Tx_Flyboy]

Re: Going from 26" to 20" 308... ?

MontanaMarine,

I highly value your inputs,

Do you think the OP would regret cutting the barrel down if he ever decided to run heavies (208AMAX, 225 BTHP, or the 210grs)?

These heavies are the key when shooting at the long lines 1,000yards+ in windy conditions.

 

[MontanaMarine]

Re: Going from 26" to 20" 308... ?

Well, in my 20.5" 308, I get 2620 fps with the 208s, and 2500 fps with the 225gr Hornady. Those speeds will carry those bullets to 1K with respectable drift numbers.

That said, the 26" will always be able to go about 100 fps or so faster.

It's all a compromise between MV and portability. The shorter tubes seem a lot easier carrying. I like the Rem varmint contour at around 22", when I cut mine to 20.5" it was because I wanted it at 22" including the brake.

If I was going to use a 308 strictly for range competitions where portability is not an issue, I'd probably go 30".

 

[ScottyS]

Re: Going from 26" to 20" 308... ?

I once cut a 26" to 20". I lost almost exactly 100 fps with 175 smk's. Don't worry about that last 50 fps, if you can't make the hit with a milder load it seems likely you're using the wrong hammer in the first place.

 

[rkgsmith]

Re: Going from 26" to 20" 308... ?

Cut our TRGs from 26 to 22 and get 2625 with the Fed 168 and 2561 with the Fed 175s. Our guys are knocking down Larues at 8 and 9 with no problems.