Shortening barrel length?

[tecumseh]

I have a 7mm RM barrel for my Encore Pro-Hunter that I got for a steal sometime back and have done some research that shows that shortening the barrel by 5" can really improve the accuracy in these barrels.

I'm going to send it off too D&T customs in Vinta OK too have the barrel shortened and the muzzle recrowned before I start to break in the barrel. Has anyone done anything like this before? And if so what where the results? I'm not going too cry if it doesn't make a huge difference since I don't have much invested in the barrel.

 

[JD338]

What is the barrel length, 26"?
Cutting it down to 21" will cut down on your performance but is no guarantee for accuracy.
What kind if accuracy are you currently getting?
Have you tried to work up accuracy loads?

JD338

 

[DrMike]

What is the barrel length, 26"?
Cutting it down to 21" will cut down on your performance but is no guarantee for accuracy.
What kind if accuracy are you currently getting?
Have you tried to work up accuracy loads?

JD338

All valid questions that need to be addressed. I'm leery of suggesting that a shortened barrel will increase accuracy. It is like saying that accuracy will improve as you decrease velocity. If that were the case, then simply use a faster powder or reduce the charge. Also, why have a magnum cartridge if you are going to settle for the velocity of a standard cartridge?

 

[ridgewalker]

In theory the shorter the barrel, the stiffer it will be. My understanding is the average loss in velocity is 40 fps for every inch removed in barrel length (give or take). If this works in your barrel it means you will lose 200 fps. Muzzle blast will probably increase due to more powder burning outside the barrel.

If you still plan to do this, I'd suggest you handload it down to 7mm-08 or 7x57 velocity because you will won't be getting the high velocity potential of the 7mm Mag and burning powder out the muzzle.

That said, it should be exciting to shoot in the dark! Big flash I would think.

 

[DrMike]

That said, it should be exciting to shoot in the dark!

:mrgreen: Ain't that the truth!

 

[Oldtrader3]

I had a 20 inch .270 Winchester (Mannlicher) and it doth bark profoundly!! The flame was impressive as well but it was accurate and I never chrono'ed it.

 

[Anonymous]

IIRC- the Pro Hunter barrels are 28" so a 5" cut would be 23" OAL.

My feeling is there's enough stuff to do to accurize a TC that I'd try it before whacking on the barrel.

 

[tecumseh]

It's a 28" barrel. I'm going to go ahead and start breaking in the barrel before I go cutting off the barrel. This is just something I was considering doing if the accuracy was poor.

 

[JD338]

I would start load development with RL 22. This is an excellent powder for the 7mm Rem Mag.

JD338

 

[Oldtrader3]

I use IMR 7828 ssc and it is very accurate and fast in my 24 inch 7mm Mag.

 

[buckfever]

You might want give retumbo a try it in that 28" barrel

 

[cloverleaf]

People dont believe that I am shooting a 250 Savage when I touch off 40 grains of 4350 from a 22inch Barrel. She barks.... I like to "Buffalo" the occasional soul who dosent know better and convince them of the ferocious power in the mighty 250. I havent shot it late enough to know what the "light show" looks like. CL

 

[Guy Miner]

I cut a 26" .30-06 down to 21" - and made it a better all-around hunting rifle by so doing. Accuracy didn't change. It was mediocre before and after.

On the other hand, a 7mm mag is a high intensity, high velocity cartridge and works well with longer barrels... I'd be loathe to cut it too much...

Guy

 

[usmc 89]

7-08 Sure cut it down, that case is a little more liberal with a shorter barrel. 7mag at 21" I would be running a fast twist barrel and using heavy for caliber bullets otherwise you will just be feeding the geese.

 

[Antelope_Sniper]

Tec, the issue is barrel stiffness. A stiffer barrel can be achieved by either making is shorter, or thicker. You will notice that benchrest barrels are generally both on the short side, and very thick.

Unless this is a match grade rifle, or a very thin barrel, I'm not sure you will notice any difference in accuracy, but you will certainly notice a difference over the chronograph.

Perhaps the bigger issue is how do you intend to use the rifle. For a woods rifle, chopping the 5 inches will make it much easier to handle, but on a plains rifles, the handling differences will be minimal.

 

[FOTIS]

That said, it should be exciting to shoot in the dark!

:mrgreen: Ain't that the truth!

Dragon's Breath! :mrgreen:

 

[Oldtrader3]

Being accurate obviously was not a function of the long barrel or now the short barrel. What do you think is causing the inaccuracy?

 

[Antelope_Sniper]

He never said how accurate it is, nor what kind of accuracy he's looking for.
Yotesmoker gets good accuracy with his and the 160gr AB's.

 

[cloverleaf]

Well, Just a couple of thoughts....and I aint no fizzasist :wink: IMHO Cutting the barrel does not actually make it stffer. It does spread the "harmonic whip" over a shorter distance in theroy, and that in theroy should make it possible for the point when the bullet actually leaves the barrel to be closer to the same point of the last shot. All else being equal form shot to shot that "could" make you more consistient from shot to shot. As I see it the trouble is "all else is never equal" and there are enough other microscopic variables to negate what you might gain in shortening that barrel. If you were talking about a 12 slug at 1400 fps muzzle lift becomes a factor, maybe, but a fast stepping 7 Mag, I doubt it. Besides, as has been stated, a A 7 mag is a lot of powder, it may benefit from a longer run to get it all burned even if you dont load it hot. But what do I know? I think this has been stated here but I just wanted to hear myself talk and see I guy with a "seven" have some success. It is a sentimental favorite for me> CL

 

[Oldtrader3]

One thing for sure, the harmonics will be different in a shorter barrel. Bending always equals the function of Moment of Inertia factoried by other attributes of shape, times length.