Threading for 7mm Rem mag and suppressor barrel length

Remington92

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Hi there all not to beat a dead horse but I'm fixing to send my rifle in for stock and action work and was going to have it threaded to support my griffin explorr 300 that's currently in jail. My question is what thread and barrel length would be safest yet maximize my 7 rem mag. Smith said at 1/2x28 the barrel will be 23.5" and at 5/8x24 they're expecting around 20'. With shortages and prices I've gotten out of reloading and have been running the hornady precision hunter 162gr eldx with good accuracy.
Will 20" and the can maintain decent velocity or will it be neutered down to a 7-08? I didn't ask about 9/16 but I suppose it'll be somewhere in the middle.
 

9.1

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How long is your barrel now and how much velocity is it getting you?
 

eric1115

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If you don't know your MV, I'd suggest that you probably aren't shooting far enough to worry about impact velocity. 400ish is probably your max range? You will have plenty no matter how short you chop it.
 
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Remington92

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Yes this rifle is more of the super lightweight variety and less of a long range gun. At 20” is 7mag an obnoxious flame thrower without the can?
 
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You'll lose about 100fps per inch you cut off.
I'm running. 7mag 20" with a can. I'm shooting the hornady 150gr cx at 2700fps. That was 3000ft in elevation.
 
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You'll lose about 100fps per inch you cut off.
I'm running. 7mag 20" with a can. I'm shooting the hornady 150gr cx at 2700fps. That was 3000ft in elevation.
I doubt it will be quite that much. I saw a 55 fps per inch reduction on a 300 win mag from 26 to 21. I made up for it with a change in load (not available to the OP) and have reduced that to a 150 fps total loss using the same bullet.

That being said, there are quite a few smiths out there that can thread and add a collar to a sporter barrel so that you can have 5/8-24 threads and a solid shoulder to mount against, regardless of how much you cut off. If your smith won’t do it, just have him do what you originally wanted it to do and then send the barreled action to one of them for threading.
 
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I doubt it will be quite that much. I saw a 55 fps per inch reduction on a 300 win mag from 26 to 21. I made up for it with a change in load (not available to the OP) and have reduced that to a 150 fps total loss using the same bullet.

That being said, there are quite a few smiths out there that can thread and add a collar to a sporter barrel so that you can have 5/8-24 threads and a solid shoulder to mount against, regardless of how much you cut off. If your smith won’t do it, just have him do what you originally wanted it to do and then send the barreled action to one of them for threading.
Your 100% correct it won't be that much I totally misspoke. I was thinking from a typical factor 24" Barrel down to 20" will be about 100fps.
Here's a good article on it.

 

RSC12

FNG
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Just trying to revive this thread a bit. I also have a 7RM and am considering cutting it down to 20". Unfortunately I live in Canada so suppressors aren't in the equation. I am also more worried about the sound, muzzle flash increase and if it will become a pain to shoot.

I'm also not too concerned with velocity loss as it would still have more than enough for what I want out to 500yrds.
 
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Remington92

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So it’s my rifles turn in the shop and options are 24” and under 1/2x28 or 18” 5/8x24. I’ve seen guys thread barrels 1/2x28 and then loctite and 5/8x24 bushing on. Would loctiting a 1/2x28 taper mount muzzle break accomplish a similar goal of adding strength to the end of the barrel? I’m thinking given my options cut the barrel to 22” have threaded 1/2x28 and use a griffen taper mount ez brake. I really wanted to use the titanium brake but it’s not available in 1/2x28 30cal.
 

Doc Holliday

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So it’s my rifles turn in the shop and options are 24” and under 1/2x28 or 18” 5/8x24. I’ve seen guys thread barrels 1/2x28 and then loctite and 5/8x24 bushing on. Would loctiting a 1/2x28 taper mount muzzle break accomplish a similar goal of adding strength to the end of the barrel? I’m thinking given my options cut the barrel to 22” have threaded 1/2x28 and use a griffen taper mount ez brake. I really wanted to use the titanium brake but it’s not available in 1/2x28 30cal.
What did you end up with lengthwise and how are you liking it?
 
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