Chamber reamer?

T

Travelor

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I have a Remington 700 in 6mmBR Norma that was built by Speedy Gonzales. Shooting factory Lapua cases, the fired case neck is so tight that a bullet will not fit back into the case neck with hand pressure - i.e. it appears to have been made with a "tight" neck reamer. I have corresponded with Speedy and it appears the barrel may have been set back at some point in life by another gunsmith as his chambers were all .272 necks per Speedy.

I have turned 100 Lapua cases for this gun so that when I seat a bullet the case neck diameter is .266" and a bullet will slip into a fired case. Accuracy is outstanding, but the gun now has 2200+ rounds through it.

My question is this:

When I need to re barrel this gun I do not want to discard these cases, so what neck diameter reamer do I specify to the gunsmith?

IIRC, there are some reamers out that throat to .265?

This is the wife's 600 and 1000 ayrd gun and I really need for it to shoot very well to keep her frustration level low.

Thanks,
George
 
If the existing chamber neck is what you want to duplicate, just take that barrel to the gunsmith that is doing your chambering for the new barrel. It will be real easy for him (or you) to use a telescope gage to measure the existing neck diameter.

PS a new barrel, and your wife, deserve new cases. Even if you have to buy them preturned, they are only about $1.50 each and new brass is more accurate that brass that has been fired 12 or more times.

100 new Lapua unturned cases= about $75.
100 new Lapua turned cases= about $150.
Is she not worth that??
 
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JerrySharrett said:
If the existing chamber neck is what you want to duplicate, just take that barrel to the gunsmith that is doing your chambering for the new barrel. It will be real easy for him (or you) to use a telescope gage to measure the existing neck diameter.

PS a new barrel, and your wife, deserve new cases. Even if you have to buy them preturned, they are only about $1.50 each and new brass is more accurate that brass that has been fired 12 or more times.

100 new Lapua unturned cases= about $75.
100 new Lapua turned cases= about $150.
Is she not worth that??
Click to expand...

Is there any evidence that a no neck turn Lapua brass .272 chamber is any less accurate than a tight neck chamber? Is turning with Lapua brass in this caliber worth while?
 
case necks

Jerry, you are right if course. I am just trying to save those precious Lapua cases I turned. The new barrel probably should have new cases. And you bet she is worth it.

Dennis, as far as a .272" neck gun, of course they can shoot great. I have a 6mmBR no-turn neck BR rifle that shot a 1.85" 5 shot group at 600 yards on the last outing. I do think that at least a little neck turning is a good thing. This group was shot with Lapua cases that I turned just enough to clean up about 75%+/- of the neck. This "claan up" of the necks showed me that the necks were not completely true - but pretty damn close after about 10 firings. With the same load and same Lapua cases not turned it was shooting in the high 2.0"'s to 3.5"'s groups at the same range.

Now if I could just do that during a Match...............

Thanks,

George
 
What strikes me is that the method of measuring neck clearance in the chamber by whether or not a bullet will slip into a fired case isn't the usual method. What with brass springback and fired case necks not being perfectly round, it wouldn't surprise me if your original chamber wasn't .272. As you measure a loaded round at .266, that's .006 total clearance with a .272 chamber. A bit much perhaps, but about what I'd expect by insuring a bullet would fit in a fired case.

FWIW
 
Charles E said:
What strikes me is that the method of measuring neck clearance in the chamber by whether or not a bullet will slip into a fired case isn't the usual method. What with brass springback and fired case necks not being perfectly round, it wouldn't surprise me if your original chamber wasn't .272. As you measure a loaded round at .266, that's .006 total clearance with a .272 chamber. A bit much perhaps, but about what I'd expect by insuring a bullet would fit in a fired case.

FWIW
Click to expand...
Charles, I'd bet what he has is a 0.272" chamber neck and a new, unfired Lapua 6BR Norma with a 88 FBLD Berger I just seated measues 0.2734".

As to the "bullet won't slip in", take that up with Tooley. That is one of his basic rules.
 
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I'm listening

I am reading your posts and understand that I have kind of reverse engineered the ammo necks. I have two other no-turn 6mmBR's and the fired brass from the Remington in the above postings is definitely smaller than that fired with the identical load with Lapua brass in the other two. (no fired cases to measure right now as it is all loaded).

Guess the next step is to do a chamber cast if I want to pursue this.

Thanks to all for the responses,

George
 
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