On a Savage Striker with 14" barrel, a friend told me I'd be smart picking a cartridge with a medium burning rate powder...say like a .308 vs a .300 WSM as the WSM would need slower burning powders & the short barrel would be less burn efficient. I always understood the powders burnt in the first few inches of barrel anyway, so cartridge consideration regarding slow burning vs fast burning powders didn't make a difference. I know length of barrel certainly affects final velocity, but that's not in question here. The former question is. Any comments/advice/info?
Thanks, Tom

The higher the expansion ratio the longer the barrel must be to burn the powder. Higher volume case with a smaller or same size diameter bore means a longer barrel to burn the powder. The 308 Winchester needs less room to burn the powder than the 300WSM because the WSM has a longer burn time and more powder to burn for example. That is why rifles chambered for magnums tend to have longer barrels. Perhaps someone can explain it more scientific than what I stated.

quote:

Originally posted by white bison:
On a Savage Striker with 14" barrel, a friend told me I'd be smart picking a cartridge with a medium burning rate powder...say like a .308 vs a .300 WSM as the WSM would need slower burning powders & the short barrel would be less burn efficient. I always understood the powders burnt in the first few inches of barrel anyway, so cartridge consideration regarding slow burning vs fast burning powders didn't make a difference. I know length of barrel certainly affects final velocity, but that's not in question here. The former question is. Any comments/advice/info?
Thanks, Tom

You are correct, the powder is burned in the first few inches of the barrel the case capacity determines the burn rate of the powder. The larger the case capacity the more speed potential ( the 300 WSM will be faster than the 308 Win) in any barrel lenght the 300 WSM can utilize a longer barrel for it's speed pontential because it has a greater volume of gas thats expands at a higher rate than a smaller case with less gas

Take a 30-30 or 45-70 in a ten inch barrel and see how much unburned slow powder will pour from a fired case. You will find only 1 or 2 fast powders will work. In a 14" barrel I would not go over the .308 and you will still have trouble. Don't let anyone blow smoke at you telling you the powder is all burned in a few inches, doesn't happen!

Simpley because you faied to ignight the powder properly has nothing to do with barrel length. Over on Long Range Hunting . com a poster has a 7MM Dakota in an XP and is getting amazing velocity and great accuracy out to 1000 yards with Widcat 200 grain 7 MM bullet

[Quote] By the buider of this XP on Long Range Hunting

"Hope you enjoy your new LR hammer. It is always fun to build these big handguns. Just for those that may be interested, top loads in my early and limited testing showed that this handgun will break 2700 fps with a 200 gr ULD RBBT and do so with 1/2 moa groups at 100 yards. Not bad !!! Will only get better from there out in range".

You need to do some more research and you will find that there is conclusive proof as to how fast the powder burns you are wrong on this one bfr

jwp475: I agree with you...I used to shoot a Lone Eagle, 14" barrel in .308 Winchester. Other than
having less velocity due to the shorter barrel, I had no problems. And the gun was deadly accurate that I attribute to the short barrel being very stiff. I used to regularly outshoot good long barrel rifles at 200 yards (scoped, of course).
Also, remembered I had an internal ballistics program that showed burning time very short..
Thanks for input...Tom

Copied from Longrangehunting.com posted by Dan B
[Quote]
Had the XP out again this evening with heavier doses of H4831SC and 162gr A-Max's. Got the velocity up to 2825fps comfortably at 63gr. With 64gr I had one shot go 2844 (bolt lift was getting heavy) and two went into the 2850's (bolt lift was again heavy but there was also an ejector mark on each case). So this was my stopping point.

I loaded a batch when I got home at 63.5gr and will reshoot tomorrow. Groups were in the .5MOA range at 100yds with each load tested this evening. Tomorrow, after a three shot'er at 100yds I'll start stretching it out to get some preliminary drop figures. Friday will be the first good LR test (at least to 500-600yds anyhow). I have 25 milk jugs waiting to get relieved of there water retaining ability![Quote]

This is a 7MM/270 WSM

Link: http://longrangehunting.com/ubbthreads/showflat.php?Cat...in=120375#Post120843