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 20 vs 24 inch barrel in .308
jmhat98  [Team Member]
4/13/2008 7:23:38 PM EST
I am looking at getting a Savage 10fp and am considering the 20", but what would I lose that I would have with a 24" barrel. Anyone got any experience or reviews? This would be my first precision rifle that is not a strictly hunting rifle. Thanks for any info.
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charliehorse794  [Member]
4/13/2008 7:51:05 PM EST
If it is chambered in .308 then you will probably not see any difference.
ARFootSoldier  [Member]
4/14/2008 5:06:43 AM EST
The only thing would be velocity at longer ranges. Might not be an issue for you at all, unless you plan to shoot a lot at 700, 800, 900, or 1k yards. The .308 starts to drop like a stone out there and velocity becomes a real issue. On cooler days, keeping a round supersonic at 1k yards from a 20" barrel may become a huge hurdle. But, if most of your shooting is inside 600-700 yards, it most likely will never be an issue.
LoneWolfUSMC  [Member]
4/14/2008 5:16:27 AM EST
If you shoot under 600 yards it shouldn't be an issue.

If you shoot to 1K and handload it shouldn't be an issue.

I have a 26" tube on my 700 right now and I have been researching cutting it back to 22".

If you are in doubt, get the longer barrel. You can always have it cut back. Ask yourself why you want the shorter barrel? If you arent going to be running through buildings or busting thick brush the 24" barrel will not be an issue. I spent a lot of time dragging around a 24" .308.

My main reason for wanting to go 22" is because I will be installing a suppressor. 26" + 8" of suppressor equals a lot of metal dragging on the ground. If I wasn't planning on suppressing this rifle, I would leave the barrel at 26" for better ballistics at long range.
SSDSurf  [Member]
4/15/2008 8:24:35 PM EST
We run 18" barrels on our Tango 51's with cans. On an 18" barrel you will see negligible differences all the way out to around the effective range of the .308 round. Tactical Operations (builders of our Tango's) found only a 30 fps difference in a 26" and 18" barrel on a chrono. Our own testing found this to be about the same.

One of the schools that we send our guys to actually tested this out to their 920 yard range. The instructor, Ryan Cleckner, found that his 18" barrel shooting the same ammo as a 26" barreled rifle only needed an extra 2 minutes of adjustment for a total of 36 minutes at 920 yards. An extra 2 minutes at 920 yards is nothing and that in itself says quite a bit about barrel length.

In essence you are not losing any accuracy but you are going to start noticing dope differences when you start stretching the .308's legs.

We are planning a long range shoot on one of the local Army bases 1000+ ranges on May 9 & 10. While our primary goal is to shoot our .50 cals we plan on accumulating our own exact data on distances for different barrel lengths, calibers and ammunition for our .308's. I will try to post some data after that.
septic-tank13  [Team Member]
4/16/2008 5:11:51 PM EST
i prefer the slight velocity boost with longer barrels. i also like the extra weight for recoil management. i'm a fan of longer barrels unless used with suppression.

if you're not going to poke out there that far, you'll probably not see a genuine difference so flip a coin. you can chop a barrel back quite a distance, but lengthening them is a bitch...
teddy12b  [Member]
4/18/2008 10:23:35 AM EST
Just to give you another opinion that's worth what you paid for it. I wouldn't worry too much about the 20" barrel getting less velocity. If you're going to shoot out to 1000 yards most guys get a 20 MOA base for that kind of shooting anyway so what another couple clicks on the scope going to do one way or the other. I've held the remington 20" 308 and it's a great balancing rifle and I assume the savage is going to feel much the same way.

I've thought real hard about getting a 20" 308 because it's something you could use at the range and eventually you're probably going to want to take it hunting anyway. All my range rifles eventually go on a hunting trip sooner or later.
LoneWolfUSMC  [Member]
4/18/2008 11:07:02 AM EST

Originally Posted By SSDSurf:
We run 18" barrels on our Tango 51's with cans. On an 18" barrel you will see negligible differences all the way out to around the effective range of the .308 round.


That is all going to depend on the load.

What load were you shooting that only showed a 2 MOA drop from a 26" rifle?

I am not doubting you, I am just curious. If I load up a 168gr BTHP with a max load of a slower burning powder I am going to see a BIG difference. If I load up with a minimum charge of a fast burning powder I may not see any change.

Also keep in mind that the "effective range" of the .308 is going to vary depending on the load. Effective range for a long barrel launching a light fast moving round is quite a bit more than lanuching a heavy high BC round.


VELOCITY is the key. We don't really care if it requires an extra couple of MOA to get to your 1000 yard target. The problem is that extra couple of MOA is because of gravity working on the round over the longer flight time due to the reduced velocity. Longer flight time means more time for wind to work on your round. More shots are missed because of improper wind calls than improper elevation.

If you are building a gun just for 1K there aren't many drawbacks to a long tube. If you are building it for LEO Sniping, tactical matches, etc. Then you have the balance the mission against the equipment.

I get way more chances to shoot at 500 yards that I do at 1000 yards right now. So I don't think I am going to loose much by having my barrel cropped back to 22". I can also handload to make up the difference.
Lawman734  [Member]
4/18/2008 2:03:44 PM EST

In my 18.5" GAP built rifle, I'm only getting 20fps less than my 22" GAP built rifle with my handload. At 800yds (the furthest I have shot the 18.5" rifle), the shorter barrel only drops 3/4MOA more than the longer barrel.

The 22" barrel is a Broughton 5C and the 18.5" is a Schneider 5P and both barrels are equipped with the same chamber.

Rougher factory barrels usually yield different results, but if I remember right-Rob01's .300WM PSS only lost a few fps when he cut his back to 22".
glockster96  [Member]
4/18/2008 3:30:41 PM EST

Originally Posted By teddy12b:
.... If you're going to shoot out to 1000 yards most guys get a 20 MOA base for that kind of shooting anyway so what another couple clicks on the scope going to do one way or the other. ....


It's not really as easy as getting a 20 moa base. With a longer tube it is easier to keep .308 factory rounds (especially 168s) supersonic at extended distances, say 800-plus yards. We were having lots of problems using Remington factory 168s out of a 20" Remington LTR with the rounds going trans-sonic at around 850-900 yards. Once that happens, accuracy goes to poop. The .308 isn't exactly an ideal 1k round (said by the guy using it as a 1k round) even on a good day. I would take any cheats you can get if you are truly going to shoot out that far.

I personally shoot a 24" Savage 10FP, and have had good results with the same Remington ammo mentioned above at 900-1K. Those 4 measely inches of barrel seem superfluous, but it can make a difference. As always, and as with anything, YMMV and I HTH.

Edited to fix a fat typing finger mistake.
SSDSurf  [Member]
4/18/2008 6:23:15 PM EST

Originally Posted By LoneWolfUSMC:

Originally Posted By SSDSurf:
We run 18" barrels on our Tango 51's with cans. On an 18" barrel you will see negligible differences all the way out to around the effective range of the .308 round.


That is all going to depend on the load.

What load were you shooting that only showed a 2 MOA drop from a 26" rifle?

I am not doubting you, I am just curious. If I load up a 168gr BTHP with a max load of a slower burning powder I am going to see a BIG difference. If I load up with a minimum charge of a fast burning powder I may not see any change.

Also keep in mind that the "effective range" of the .308 is going to vary depending on the load. Effective range for a long barrel launching a light fast moving round is quite a bit more than lanuching a heavy high BC round.


VELOCITY is the key. We don't really care if it requires an extra couple of MOA to get to your 1000 yard target. The problem is that extra couple of MOA is because of gravity working on the round over the longer flight time due to the reduced velocity. Longer flight time means more time for wind to work on your round. More shots are missed because of improper wind calls than improper elevation.

If you are building a gun just for 1K there aren't many drawbacks to a long tube. If you are building it for LEO Sniping, tactical matches, etc. Then you have the balance the mission against the equipment.

I get way more chances to shoot at 500 yards that I do at 1000 yards right now. So I don't think I am going to loose much by having my barrel cropped back to 22". I can also handload to make up the difference.


I agree that velocity is key and even at 920 yards this test was only seeing a 2 MOA difference. So at that range I would believe that there is only a nominal difference in velocity. Our rifle maker (Tactical Operations) only got around 30fps difference on a 26" barrel and an 18" barrel with 168gr Federal Gold Sierra Matchking. For our purposes we do not hand load and also shoot the gun makers suggested 168gr Federal Gold Sierra Matchking. We also did our own chrono test and also only got around 30fps difference with this round on a 26" barrel and the 18" barrel so those velocity claims are accurate.

I did not do the shooting nor did I witness the 2 MOA difference in the drop at 920 yards from a 26" barrel and a 18" barrel. This was done by an instructor at a school that we send our new guys to. He took the same rifle and kept chopping the barrel and accumulated data. The rounds used were the Black Hills 175gr match ammo. He did relate that the 168gr Federal Gold Match was, I think a bit more difference from the Black Hills. Here is the article www.sniperschool.com/sniper-rifle-barrel-length

I had partners that attended the course and witnessed this, so I have no reason to disbelieve it. However as I mentioned, on the 9th and 10th of may we have a 1000+ yard range reserved on one of the local military bases and while this is mainly to shoot our .50's, we are planning to shoot different barrel length .308's with different rounds to accumulate some first hand data at longer ranges. So I will get to see this for myself.
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