My 30BR Reamer

jackie schmidt

jackie schmidt

New member
I have has several inquiries about my 30BR reamer, so I am going to answer them all here.

My reamer is the same as the originol Robinett except for the overall chamber length. The length of the chamber that this makes is 1.550 inch. This is a product of the way I make a 30BR case.

I blow them out, rather than the more common method of necking them up.

I took a regular 6mm barrel and put a standard 6BR chamber in it. I then take a .330 reamer and ream the neck portion of the chamber out.

When you fire a full loaded 6BR round in this chamber, what comes out is a perfectly formed and straight 30BR case, ready for neck turning. Since I am blowing the case out rather than pushing it back, it retains much of the originol 6BR length. So, I had a reamer ground to accommodate this rather than trim all that length off. In short, it's a 30 BR with a longer neck.

Here is a picture of a case the way it comes out of the "blowout" barrel.

Pretty, ain't it.
http://benchrest.com/attachment.php?attachmentid=15817&stc=1&d=1421986164
 

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Several seasons back, Jackie sent me samples of his cases, which, indeed are very nice! :) If one has a worn out 6BR, PPC (would need to re-chamber), or, other 6mm barrel to dedicate, and the ability to chamber, or, open the chamber-neck diameter, Jackie's method appears to be, "the cat's meow".

The biggest 'advantage' appears to be the 'donut' free dead-straight necks; the extra [neck] length - about 0.040" doesn't significantly increase powder capacity. For people who do not like, or, are uncertain about their case preparation, this is a very attractive method. ;) RG
 
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R.G. Robinett said:
Several seasons back, Jackie sent me samples of his cases, which, indeed are very nice! :) If one has a worn out 6BR, PPC (would need to re-chamber), or, other 6mm barrel to dedicate, and the ability to chamber,or, open the chamber-neck diameter, Jackie's method appears to be, "the cat's meow".

The biggest 'advantage' appears to be the 'donut' free dead-straight necks; the extra [neck] length - about 0.040" doesn't significantly more powder capacity. For people who do not like, or, are uncertain about their case preparation, this is a very attractive method. ;) RG
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So, if you had a barrel with a 6PPC chamber could you just re-chamber without setting back? I haven't had my morning coffee yet so my mind isn't up to full speed yet.
 
adamsgt said:
So, if you had a barrel with a 6PPC chamber could you just re-chamber without setting back? I haven't had my morning coffee yet so my mind isn't up to full speed yet.
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It looks like simply setting-up, running a 6BR reamer into the PPC chamber, and then opening the neck diameter should work.:eek: Remember - if ya do this, you MUST use 6MM/.243 bullets to fire-form! :eek: RG
 
R.G. Robinett said:
It looks like simply setting-up, running a 6BR reamer into the PPC chamber, and then opening the neck diameter should work.:eek: Remember - if ya do this, you MUST use 6MM/.243 bullets to fire-form! :eek: RG
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That's the only down side I see. It creates the "potential" issue of mistakenly trying to send a 30 Cal bullet down a 6mm bore. Otherwise, I like the method and have done it.
 
mwezell said:
That's the only down side I see. It creates the "potential" issue of mistakenly trying to send a 30 Cal bullet down a 6mm bore. Otherwise, I like the method and have done it.
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If you only ream out the neck area, you would have to push the 30 bullet pretty far into the case to get it to chamber, no?
 
"The biggest 'advantage' appears to be the 'donut' free dead-straight necks"

The outside of the neck would be nice and straight, but would the brass still not be thicker at the base of the new neck on the inside, since you've just some of the shoulder into the neck?
 
1 have a special little fire forming rig that I use in back of my shop. I fire it into a large insulation roll straight into the ground. You cannot load a regular 30 BR into it. Remember, at the end of the neck is a 6mm bore.

Many of my friends in this area use my reamer, they will come over and blow out a bunch of cases on occasion. You can do 100 in about an hour.

As for any donut, there never is one after neck turning, but even if there was, a typical bullet used in the 30BR never gets near it.

Also, I do this strictly for convienience. It is so easy to make perfect cases like this. But, as far as it shooting any better, or worse, than the standard Robinett, I seriously doubt anybody could tell the difference.
The cases do come out so good that I might just try a "no neck turn" 30BR, just for the fun of it. I can make a similar little fixture that would allow my to ream my .330 chamber out to what ever it would require.
 
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You guys are picking my comment apart. First, I said it was "potential", as far as putting a 30 in the chamber. Of course the bullet would be pushed back. That doesn't stop "Murphy". Second, a neck turned loaded 30 br round would certainly chamber in it, albeit, it would have to push the bullet back.

I'm not knocking Jackie's method at all, just pointing out that some ham-fisted dummy could put a fully prepped 30 round in and it fire. That won't work out very well, I'm guessing. Unless doing the work yourself, I'd also guess some smiths would be reluctant to do it.

Alternately, you could rattle a 6mm bullet down a 30 barrel or use the pistol powder/ cream of wheat method without the same risk. With proper charges and powders, I believe any of the three methods work equally well.

Carry on...
 
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I think the longer necks would equal more consistent neck tension. A bullet with large pressure ring i dont trust in that short of a neck b
 
sdean said:
How are you going to seat a 30 cal bullet in a 6br case?
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Crazier things HAVE been done - like the old Precision Shooting article, complete with pics of the wreck created by a fellow who managed to chamber a fire a 7MM round of some sort in a .224 chambered barrel! That particular bullet got LONG! :p Running the neck reamer in too deep could lead to trouble! :eek: Just do it safely and consider ALL possibilities - and do not have any 30 Cal bullets handy when the FF barrel is on the action! :eek: RG
 
mwezell said:
You guys are picking my comment apart. First, I said it was "potential", as far as putting a 30 in the chamber. Of course the bullet would be pushed back. That doesn't stop "Murphy". Second, a neck turned loaded 30 br round would certainly chamber in it, albeit, it would have to push the bullet back.

I'm not knocking Jackie's method at all, just pointing out that some ham-fisted dummy could put a fully prepped 30 round in and it fire. That won't work out very well, I'm guessing. Unless doing the work yourself, I'd also guess some smiths would be reluctant to do it.

Alternately, you could rattle a 6mm bullet down a 30 barrel or use the pistol powder/ cream of wheat method without the same risk. With proper charges and powders, I believe any of the three methods work equally well.

Carry on...
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Yes - all of this - there is the potential for serious trouble - just use your head! )chill:)) RG
 
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