Barrel length and powder burn rate for 7 mag.

[stonehands1]

I've had the best groups with 7828 in my 7mags with 180 eldms. Come to think of it all the 7mags I've done load work for liked it. My neighbor has 3 of them and has also had good luck with 7977.
24 inch works great with 175 class bullets.

 

[DJ Fergus]

I'm fixing to do a re-barrel on my 7mag. I can get a 24" barrel right away. 4-6 month wait for a 26"

Question is, will 24" work with my current components ( I know I'll have to re-work it for the new barrel) Currently I run a 26" barrel with 175 gr LRAB w/67.7gr of H1000. Will the H1000 be too slow in a 24" barrel? I have a fair amount of H1000. Not much of any other powders. couple # of H4831sc and H4350. Regardless I plan to stay with the 175gr class bullets and would like to keep using H1000. Obviously if things were more normal I'd just get a different powder and start over.

Do I go with the 24" or should I order the 26" to work with the H1000 better?
Other powder recommendations for the 175gr class bullets that might work better than H1000?

Thanks,

Everyone has their own likes and opinions. Personally for me, 26" without a doubt.

 

[Wrenches]

I have a factory 700 CDL in 7 mag with a 26" barrel. I'm just now starting to work with 175 grain bullets and 8133 powder. I have only fired 9 rounds so far while starting a ladder up test, but it does show some promise in velocity and accuracy. I will post here if I settle on a load.

 

[thatguyshm]

Twist rate? Purpose? I use a 26" on my 7mm and had thought many times to cut it down. I hunt in Colorado for elk so I want all the velocity I can get. In Maine, realistically no need for the extra length. I have taken two deer so far this year and both were in low light situations, and both times I still got a decent muzzle flash using RL23 and a hammer hunter.

I'm honestly looking at getting the Savage Ultralight in 280 AI since it comes with a 22" barrel. Most of my hunting here doesn't require the extra four inches of barrel, longest shot I have is about 310 yards, and that hammer pole axed a small one at that distance this year.

 

[TRG65]

Went through a similar dilemma a few months ago. The key for me was the can I intend to use. 26" and a can gets long and unwieldy, aka my match rifle. So I had bugholes order a Bartlien cf mtu in 22". I think it was about 4 months. The action is there being chambered now. It is going to be a 7RM. My goal is only a 160 accubond at 2950'ish.

 

[BillyGoatGruff]

Twist rate? Purpose? I use a 26" on my 7mm and had thought many times to cut it down. I hunt in Colorado for elk so I want all the velocity I can get. In Maine, realistically no need for the extra length. I have taken two deer so far this year and both were in low light situations, and both times I still got a decent muzzle flash using RL23 and a hammer hunter.

I'm honestly looking at getting the Savage Ultralight in 280 AI since it comes with a 22" barrel. Most of my hunting here doesn't require the extra four inches of barrel, longest shot I have is about 310 yards, and that hammer pole axed a small one at that distance this year.

Looking for an 8 twist or 8.5. Purpose is hunting. Like I said previously, I do have a can to put on it. I'm in Colorado. So long shots are always a possibility

 

[dogz]

Couple quick thoughts:

First off, build for balance that suits you.

Next up, a difference in barrel length of 2" will change speed roughly 50 fps total.

Lastly, being as you're going with a can I'd no doubt lean towards the shorter barrel.

I've had Big 7's in 23" to 26" inch, at my size (6'1" and 212) I've come to enjoy 25". But, in all honesty they'll all do.

 

[BillyGoatGruff]

It will burn the powder just fine.
I do not know what you mean by you are at max case capacity.
A longer barrel will not burn the powder more efficiently until you get to 30" and above.
A 24" barrel will work just fine.

Cheers.

By case capacity, I mean in my Berger manual w/ H1000 175gr bullet and the 67.7gr I've been running. it says that that's 103% fill ratio. That's what I meant by max case capacity. Don't know if that's the correct term or what that even means exactly? Loads fine and no pressure signs.

 

[MagnumManiac]

By case capacity, I mean in my Berger manual w/ H1000 175gr bullet and the 67.7gr I've been running. it says that that's 103% fill ratio. That's what I meant by max case capacity. Don't know if that's the correct term or what that even means exactly? Loads fine and no pressure signs.

I know what you mean now. All good. The term is case fill percentage.
Don't be scared to run compressed loads, they often give the best accuracy.

Cheers.

 

[Longtine88]

I run 24" on mine. Never had an issue with flame throwing, slow velocities or the such. I shoot 180 Hybrids at 2,970' with a Sendero Light contour. You don't have to have the 26". You might be lucky and gain 30 or 40 fps but that's it. Crap I even have a 22" 300 Win Mag that shoots 215's at 2,930'. So don't let the 2" difference scare you off. I'd pull the trigger.

 

[willtim]

My 7 mm RM has a 24 inch barrel. I have no issues.

 

[BillyGoatGruff]

I decided to go with the 24".
Being a touch shorter should help with the suppressor and overall length, plus maybe add a little stiffness.
Plus it was in stock and I can get going on the re-barrel sooner.

If anyone has experience with 175gr projectiles and different temp stable powders other than H1000 I'm open to recommendations .

Thanks everyone for your replies. I appreciate it.
BGG,

 

[thatguyshm]

Low 60s with RL23

 

[ormandj]

I'd have gone down to 20", personally. I shoot suppressed and hate carrying anything beyond that with the TBAC on the end. N565 might be another option for you. RL23 is the other one. I'm going down this path, just with a 7SS. The two mentioned powders will be around H1000 burn rate and relatively temperature stable (RL23 is most, N565 next most). Every cartridge is different, so see what others have gotten out of one with those powders. The burn rate charts rarely tell the whole story.