chambering BRX with 22 BR Reamer

[NZVarminter]

I cant find a BRX reamer over here in New Zealand, but I do have a 22 BR reamer. The BRX is the BR with the shoulder pushed forward 0.10".... so will it work to run a 22 BR reamer in 0.10 deep, and then cut the throat separately?

Looking at the dimensions, my 22 Br reamer is 0.471 at the base and 1.071 to the shoulder at 0.461.

So 0.010 taper over 1.071.

So the numbers are 0.010/1.071*1.171=0.011

so running the reamer in deep will mean 0.001" larger at base and shoulder.

Does that make sense?

Thanks in advance

Grant

 

[boltfluter]

Grant, yes it does make sense. I have done a similar thing by running an older .22 BR. reamer in .060 deep, to take advantage of the .060 longer brass. Worked just fine for me. Gave me a mini BRX so to speak. I see no reason why your idea would not work just fine.

Paul

 

[Stan Taylor]

Well my first question is which brx chamber are going for.

 

[AlNyhus]

The BRX is the BR with the shoulder pushed forward 0.10".... so will it work to run a 22 BR reamer in 0.10 deep, and then cut the throat separately?

Done this way, there will be .100 of neck diameter freebore before the throat begins.

That is a sure fire accuracy killer. -Al

 

[NZVarminter]

AINyhus..as the chamber is 6mm bore and cut with 22 reamer, the neck is not being cut but the initial reamer, and needs to be cut separately after so I can specify whatever freebore I want...probably 0.1-0.12" should be right for 105's

 

[AlNyhus]

AINyhus..as the chamber is 6mm bore and cut with 22 reamer, the neck is not being cut but the initial reamer, and needs to be cut separately after....

Got it. Didn't see in your original post that it was a 6mm barrel.

 

[gunsandgunsmithing]

AINyhus..as the chamber is 6mm bore and cut with 22 reamer, the neck is not being cut but the initial reamer, and needs to be cut separately after so I can specify whatever freebore I want...probably 0.1-0.12" should be right for 105's

What's the neck diameter of the 22br reamer?

AINyhus..as the chamber is 6mm bore and cut with 22 reamer, the neck is not being cut but the initial reamer, and needs to be cut separately after so I can specify whatever freebore I want...probably 0.1-0.12" should be right for 105's

I admit that I didn't see the 6mm part at first but I don't see a problem either. I've done similarly to make other chambers like a 30-284, using a 6.5-284 reamer, a neck diameter chucking reamer and then throat it.

 

[Stan Taylor]

What's the neck diameter of the 22br reamer?

I admit that I didn't see the 6mm part at first but I don't see a problem either. I've done similarly to make other chambers like a 30-284, using a 6.5-284 reamer, a neck diameter chucking reamer and then throat it.

All I can say is his 22br reamer better be smaller than .244 neck an I kind of doubt it.

 

[gunsandgunsmithing]

All I can say is his 22br reamer better be smaller than .244 neck an I kind of doubt it.

I do believe you're right Stan. I thought about that and talked myself out of it. Lol! You can't push the shoulder forward without pushing the neck forward. As long as the neck diameter is as Stan said, .243ish...it'll work. Or, the throating reamer would have to be big enough to cut that out. There is some .243 neck 22 stuff out there, though.
And we're talking, the neck diameter of the reamer better be what it says, i.e. .243.
Thanks for setting me straight Stan.--M

 

[Stan Taylor]

We'll now that the OP has give the rest of the story here is my opinion if your going to improvise overcome an adapt do it right. Well here goes if I was going to do what your doing I would headspace a 6mmbr an I would have found a 20 br reamer an proceed accordingly you wouldn't have a issue with throat or anything my guess your 22br reamer is about .253 neck that's a flat no no. That's my 2 cents

 

[Stan Taylor]

I do believe you're right Stan. I thought about that and talked myself out of it. Lol! You can't push the shoulder forward without pushing the neck forward. As long as the neck diameter is as Stan said, .243ish...it'll work. Or, the throating reamer would have to be big enough to cut that out. There is some .243 neck 22 stuff out there, though.
And we're talking, the neck diameter of the reamer better be what it says, i.e. .243.
Thanks for setting me straight Stan.--M

Well I give my 2 cents to the OP I hope he thinks about it thanks Mike.

 

[gunsandgunsmithing]

We'll now that the OP has give the rest of the story here is my opinion if your going to improvise overcome an adapt do it right. Well here goes if I was going to do what your doing I would headspace a 6mmbr an I would have found a 20 br reamer an proceed accordingly you wouldn't have a issue with throat or anything my guess your 22br reamer is about .253 neck that's a flat no no. That's my 2 cents

I'm wondering if this was a test...and I failed. Lol!

Bottom line, Stan is right and unless the neck diameter of the 22br reamer is smaller than the barrel's groove diameter....the op won't like the end result....More specifically, smaller than the 6mm throater, for the 22br neck to clean up.

 

[boltfluter]

My mistake. I was assuming the end product was going to be a .22BRX .

Paul

 

[Stan Taylor]

We'll I hope this helps the OP on his finished project I measured the neck on my 20 br reamer it's right at .235 od neck an my 22br reamer is a .254 neck I think if you can find a suitable reamer you are in pretty good shape.

 

[AlNyhus]

All I can say is his 22br reamer better be smaller than .244 neck an I kind of doubt it.

Yep.

 

[swd]

Are you going to build another 22BR? If not it's really easy to take it to a machine shop and grind the neck down under bore diameter. It's less than 10 minutes on a surface grinder with a spin fixture.

 

[NZVarminter]

SWD...not a 5 min job in NZ...

Had a talk with my Gunsmith and he pointed out that if the 6BRX chamber is cut with a 22BR reamer, then there will be a sharp shoulder at the shoulder/neck junction that will need rounding off somehow.. a few too many potential issues that are not conducive to maximum accuracy!

JGS has a 6mm BRX reamer in stock, so its now in the post to me.

Thanks for all the suggestions