7mm rem mag barrel length

[Tc343]

I'm looking at having my Rem 700 28" 7mm rem mag barrel chopped down to 24". Are there any real downsides to this other then some minor FPS loss? From what I have read i'm under the impression if I stay 24" or longer I should be fine.

Thoughts????

 

[dugsagun]

My dads 24" 7mm remmag brwn bar usually posts velocities about 100fps less than advertised. Which at 200yards, his max imposed range, equates to about .1" more drop with hornady 139g load for deer. I would bet u would be just fine at 24".

 

[ruger7722]

more muzzle blast depending on powder used.i would rather have 24 though

 

[Bansheewarrior]

As long as you stay at or over 24" you will not see a loss in performance under that you will not be getting your full effect of your weapons available power. Around 22" you might as well be shooting a 270 win because you will be getting about the same performance with the less recoil of the 270. We had an experiment while back here at home proving just this with my and a buddies 7mm mags and my 270. Shooting at some plate steel same ammo out of the 7mm the long barrel proved a lot more powerful then pulled out the long barreled 270 and it performed better than the short 22" 7mm mag but not as good as the 24" barrel was using a 26" barreled A bolt 270 win. Unscientific and just going off damage and penetration on the plate steel we were shooting but between the three there was noticeable difference.

 

[Bansheewarrior]

Side note we didn't set out that day looking to see the differences between the two 7mm we set out that day trying to see the differences between factory loads and hand loads we had made up when we stumbled on the differences between the two rifles with same rounds. Funny how things turn up sometimes.

 

[6mm Shoot]

I am not knocking what you are doing. It is my understanding that all the magnums need a 26" barrel or better to get the full potential out of the caliber. That is why you are spending top dolor for the round. Your 28" barrel is giving you 400 fps over the 7mm-08.

If you want a shorter barrel you should go to the 7mm-08. With a 24" barrel In 7mm mag and a 24" barrel in 7mm-08 there is only 200 fps difference in the same bullet weight. Plus the ammo is cheaper in 7mm-08. If you reload it is cheaper to load the 7mm-08. Less powder and cheaper primers.

As to answer your question you can shorten your rifle to any length you want and it is just going to cost you fps and a bigger fire ball.

 

[william]

Mine's longer than yours! Just saying...

 

[Hohn]

I don't think the FPS loss down to 24" is a big deal. But why do it? It's one thing if you are a benchrest guy and are getting the barrel set back to get a new throat out of the deal. But if you just want something shorter?

I dunno. It doesn't make sense to me, but it seems pretty innocuous either way.

 

[whitetailbowhunter]

i was always told that my 7mm Rem Mag needed at least 26 inches of barrel to reach it's full potentiel. But then again, i don't think it would completely "ruin" the accuracy/fps/etc.

 

[Hookeye]

Hmmmm, I had a 700 BDL in 7mm Mag.............late 70's model.
Coulda swore it had a factory 24" bbl.............

 

[Hohn]

Hmmmm, I had a 700 BDL in 7mm Mag.............late 70's model.
Coulda swore it had a factory 24" bbl.............

I've read of some testing done on a .338 Lapua that showed good accuracy and only tiny small velocity penalty with a barrel as short as 22".


That's a heavier bullet, true-- but a LOT more powder, also. Anyway, this is my basis for thinking 24" on a 7mm RM is not a big deal.

H

 

[Hookeye]

FWIW IIRC the 7mm Remmag was designed to run a 175gr (high BC bullet) on elk at distance.

How much case capacity is lost % wise when running longer bullets like that in let's say a 7mm-08? Plus Remington short actions are reportedly kinda short.

I had a 7mm08 and a 7mm Rem mag. Sold them a long time ago.

Been eyeing another old used 7mm mag lately..........in case I ever go after elk.

 

[Yeah]

You'll lose 100-120 fps going from 28" to 24", depending mostly on powder. I've cut a handful of 7 Mag tubes and were I in your shoes I'd be aiming for proper balance as it trumps the velocity loss by a wide margin. The last 7 Mag I spent much time shooting was at 22" and could send a 162 Amax at 3000 fps.

A 162 AMax has a length of 1.417" and a svelte profile with a long boat tail. In most of the Remington 7-08 factory chambers I have (which is plenty as 7-08 was once my go to utility round) a COAL of around 2.85" gets the bullet square in the lands. That seating consumes just over 9 H2O grains of case capacity, of the available 55 (Lapua hulls).