Gunsmith question, 7mm RM reamed to 28 Nos?

[DJ Fergus]

I've got a 26" krieger on a 700 action that's been trued. 7mm RM. If I had it reamed to a 28 Nosler, would the barrel have to be set back? I don't want to lose any barrel length. I will leave it a 7mm rem mag if I'm going to lose barrel length. Not a problem with leaving it 7mm rem mag but I already have 2 other 7 rem mags.

 

[joseph singleton]

LOL,,problem SOLVER HERE,,,,I'll take one,, ,couldn't help myself....

 

[MagnumManiac]

A 7STW will clean up the chamber without a setback, but I ALWAYS setback 1 turn of the threads to make sure I get all the throat cleaned up.
The 7RM is 2.228 to the neck/shoulder and the 28 Nosler is 2.31, so it will clean up no issue.

Cheers.

 

[can1010]

the only problem would be if the two had different neck diameters, then you might have to setback your barrel only other consideration is if you have major firecracking in your barrel

 

[elkaholic]

I'm not a smith but I think the only problem could be if the neck diameter happened to be greater than the Nosler.

 

[MagnumManiac]

The Nosler is thicker in the neck, .3150" for the 7RM and .3200" for the 28 Nosler.

Cheers.

 

[shortgrass]

A simple re-chamber isn't all that will be needed for this conversion. You'll have feed issues to deal with, too. Not a huge problem, but worth mentioning none the less. I see this all the time. It's not a "all ya' gotta' do" type thing to make it work properly.

 

[L.Sherm]

Why not go 30 Nosler? Is it a factory barrel your setting back?

 

[shortgrass]

Re-chambering a barrel depends greatly on the condition of the barrel. The inside needs to be 'squeaky' clean and then bore scoped for condition. Factory barrels are usually not worth re-chambering, but yours is a Krieger. Setting a 700 or 70 back 1 turn means loosing 1/16", not enough to be concerned about, IMO. Even 2 turns means nothing in terms of velocity loss.

 

[Chamberman]

If you already have two other 7 Rem Mags why not do it.
I agree with shortgrass, you will want to have that neck and throat area cleaned up by setting it back a couple turns.
It will make no difference on speeds or stabilization if that is your concern.

 

[Rflshootr]

When I do a set-back, I always set back the length of the neck. This assures a complete clean up of the chamber and a nice new throat.........unless the barrel is shot out. Then it isn't worth even considering the time and effort.

 

[MagnumManiac]

The only factory barrels I will re-chamber are new, if it's been fired, I won't do it.
I have done 2 for myself with a perfect outcome on both.
A Win Model 70 Classic Stainless in 375 H&H I bought specifically to re-chamber to 375 Weatherby, and my Sendero II in 7RM that I re-chambered to 7STW. I really like the parallel throat on the STW, being 1/2 a 'thou over bullet diameter just works. I have used this on several cartridges now and it works for longer than a tapered leade.
The primary barrel is a custom 29" 1:8" twist 264WM, the STW is just for laughs really, cuz I can't stand the 7RM! Have had so many hunters in camp bragging about their 7RM and when I dump a deer with the 300 and their legs fall out from under them they STILL say, oh the 7's shoot flatter!

Cheers.

 

[L.Sherm]

Setting back the barrel is probably gonna cost the same as chambering a new barrel unless you can do it yourself

 

[DJ Fergus]

I've got an STW. I think I'm just going to leave it a 7mm RM . Its a krieger barrel. I haven't shot it but I did bore scope it. It looked good. I've had it for a long while but never shot it. I've loaded for enough 7mm rem mags that its not much of a deal for me anymore. Thanks to everyone for the input.