To shorten or not to shorten?

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Captain Ron

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I have a Browning x bolt in .338WM with 26" barrel I find that it seems too long and gets in the way and was wondering what the pros and cons are about shortening it.
Will I lose or gain accuracy? How much velocity will I lose? How short should I go?
Should I just sell it and start with something shorter? :confused:
 
You will lose very little velocity... nothing that matters in a factory hunting rifle. Some guys cut them to 22 inches. Accuracy will not suffer.
 
I would leave it alone. Whats the point of cutting it short?? The whole point of the magnum is you can pack a bunch of slow-burning powder in there. Cut the barrel and you can't burn all that powder anymore. Shorter barrel will also increase muzzle blast, and the weight reduction would theoretically increase felt recoil, but I doubt that would be significant enough to notice.

If you want something handier, get a cartridge that is designed for such purposes (35 whelen perhaps?)

The rule of thumb seems to be 25-35 fps per inch of barrel cut off with most calibers...So you are probably losing 100-150 fps chopping off four inches. Maybe more in the magnum, because these numbers reflect a cartridge that can use all its powder in a shorter barrel, like a 30-06 or 270.
 
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I would shorten, without hesitation, but just a couple of inches at a time. Try 24", or 23 1/2", and see if you like that. It's easy to take more off, but you can't put it back on if you go too short.
 
Long ago, one of the gun rag writers tested velocity loss by barrel length reduction. Forget which guy(Layne Simpson, I think) and the calibre. The guy fired a test group then cut 1" off and re-shot. He found you lose about 100 FPS per inch of barrel. Not 25 to 35 per inch.
Cut too much off and you have a lot more of the excessive muzzle blast and noise you have now. And you end up with a large calibre with lots of felt recoil, muzzle blast but without the velocity magnums need.
However, out of a .338 WM, a few hundred FPS less won't make any difference to whatever gigantic beastie you shoot. Accuracy will not suffer as long as the barrel is correctly re-crowned.
 
sunray said:
Long ago, one of the gun rag writers tested velocity loss by barrel length reduction. Forget which guy(Layne Simpson, I think) and the calibre. The guy fired a test group then cut 1" off and re-shot. He found you lose about 100 FPS per inch of barrel. Not 25 to 35 per inch.
Cut too much off and you have a lot more of the excessive muzzle blast and noise you have now. And you end up with a large calibre with lots of felt recoil, muzzle blast but without the velocity magnums need.
However, out of a .338 WM, a few hundred FPS less won't make any difference to whatever gigantic beastie you shoot. Accuracy will not suffer as long as the barrel is correctly re-crowned.
Click to expand...

I would seriously question his results...

Lymans and Remington have both tested this and released the info in various reloading manuals and product catalogs. The general rule is faster cartridges lose more velocity per inch.

A 2000fps cartridge will only lose around 10fps per inch, while a 3500 fps cartridge will lose 30-40 fps. For instance a 130 grain 270 loses 37fps per inch going from 24 inches to 20.

Chuck Hawks summarizes it here, at the bottom of the page. http://www.chuckhawks.com/rifle_barrel.htm

edit - just noticed Im responding to Sunray. No wonder his 100fps per inch sounds like bullcrap... no wait, we decided the other day hes a bird that drops guano didn't we? lol
 
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sunray said:
Long ago, one of the gun rag writers tested velocity loss by barrel length reduction. Forget which guy(Layne Simpson, I think) and the calibre. The guy fired a test group then cut 1" off and re-shot. He found you lose about 100 FPS per inch of barrel. Not 25 to 35 per inch.
Cut too much off and you have a lot more of the excessive muzzle blast and noise you have now. And you end up with a large calibre with lots of felt recoil, muzzle blast but without the velocity magnums need.
However, out of a .338 WM, a few hundred FPS less won't make any difference to whatever gigantic beastie you shoot. Accuracy will not suffer as long as the barrel is correctly re-crowned.
Click to expand...

Flawed info from sunray ... ignore...

Cutting 2 inches off my 338-06 (24 to 22) with a 225 grain bullet reduced velocity 10 feet per second. From about 2720 f/s to 2710 f/s (with 2 inches cut)
 
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Here is an old thread where I went through the same debate regarding shortening the 25" barrel on my .375 H&H.

At the time some guys were saying that cartridges with certain bore to case capacity ratios did not lose a lot of velocity when you cut off a few inches of barrel length. This was what happened in my case YMMV.

http://www.canadiangunnutz.com/foru...port-with-velocities/page2?highlight=brno+602

The results from my range test below:

I finally got to the range today and tested the ZKK 602 carbine.

Chronograph setup was 20' from muzzle. I started at 15' but the chrony didn't seem to like the muzzle blast

Federal Power Shok 270 gr SP:
25" barrel: 3 shot average: 2700 fps
20" barrel: 8 shot average: 2638 fps
Velocity loss: 62 fps

Winchester Supreme 270 gr Fail Safe: I didn't test this load prior to shortening the barrel so I'm listing the factory data.
24" barrel: 2670 fps
20" barrel: 3 shot average: 2599 fps
Estimated velocity loss: 71 fps

The recoil from the carbine was stout from the bench. Even with the Past recoil shield, a dozen rounds was about all my shoulder would take.

Conclusions:

The average velocity loss resulting from shortening the barrel from 25" to 20" was 66 FPS.

The recoil and muzzle blast is strong but manageable, especially when shooting off hand. The muzzle flash was visible in bright sunlight and may be a factor in low light conditions.

The carbine points and handles much better than the rifle. The LOP seems to be fine as is.

The express sights seem to be printing absurdly low at 100 yards with the 100 yard leaf. It's probably my inexperience using express sights. I am going to experiment with different bead sight pictures at 25 yards before I do anything drastic. If I decide to replace the present front brass bead, I'll probably just go with a lower sight with a slightly larger brass or white bead.

I am very pleased with how this high powered carbine turned out.
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I fixed the express sight problem by installing a lower front sight. It shoots to POA at 100 yards now with the 100 metre leaf.
 
A looooong time ago hunters and gun writers were wanting long barreled hunting rifles, well we've went that route and most hunters found the 26" barrel too cumbersome and awkward.
The new short magnums have a 23" barrel and I like that for carrying. I've found they work just fine on game.
 
sunray said:
Long ago, one of the gun rag writers tested velocity loss by barrel length reduction. Forget which guy(Layne Simpson, I think) and the calibre. The guy fired a test group then cut 1" off and re-shot. He found you lose about 100 FPS per inch of barrel. Not 25 to 35 per inch.
Cut too much off and you have a lot more of the excessive muzzle blast and noise you have now. And you end up with a large calibre with lots of felt recoil, muzzle blast but without the velocity magnums need.
However, out of a .338 WM, a few hundred FPS less won't make any difference to whatever gigantic beastie you shoot. Accuracy will not suffer as long as the barrel is correctly re-crowned.
Click to expand...

While sunray may be off a bit on the velocity change the rest isn't rot: I remember that article in a G&A magazine oh probably early '90s and the author had a special order barrel of several feet length. If memory serves me, it was chambered for a pistol caliber (32acp??) This may have limited relevance to the present discussion but the result of the test: Original barrel configuration, the round could not fire the bullet completely out the barrel each shot (predictably for the lengthy barrel used) and as the barrel was shortened bit by bit, the optimum length was achieved before velocity started dipping again (seem to recall it being around 2'). I'm sorry, I wish it was fresh in my memory or I knew where the article was.

I expect the manufacturer of the OPs rifle selected 26" as an "optimum" for the intended use: While a 338 would likely provide the most efficient delivery with a few more inches of barrel length, as the author says this would become impractical for hunting use. Personally I have carried my twelve pound target rifle in the field because I can: While I wouldn't cut my own barrel down any, ultimately it is your rifle and you must live with how it is. Collate all the facts you can, and make the informed decision about this rifle or what other application it could be used; without regard for asinine fads.
 
I remember the article in American rifleman? publication of the bra. They started with a 26" 270 shooting a max load of 4831 not sur which and went in 1" increments to 20' recrowned after each step the load stayed the same and the average loss throughout the test was in the order or 20 fps/inch. Now there was less loss going from 26 to 25 " and more from 21 to 20" so it don't know where you 100fps/in comes from. The 300wm is probably less overbore and I would expect losses to be similar. 2" more maneuverability for 40 fps seems like a good trade to me.
 
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