6.5 X 47 ---Flasholes

Here is a quote from Tony Z, an Australian shooter:

Here is my two cents worth. From what i have seen of my own and others combinations, when it comes to small primers and some cartridges, there seems a need to go to the 450 mag primer. Now that should tell most of us that all is not well.
I had a 6BR once, it showed plenty vertical at long range, and even short, with the 205M, so i went the 450 route and the vertical closed up. Powder was the usual Varget, pills were 107 SMKs and all in a 700 action that had been bushed back to the 62 thou firing pin. Spring preload was 19 lb. I adjusted the spring to a stock Rem item at 26 lb preload. Nothing changed. So out of frustration i took 12 BR cases, reamed the pockets to accept LRPs and the problem went away. Now i know very well that this is very unusual in a 6 BR.

It doesn't end there. With better things to do with my time than ream 6BR primer pockets to LR, i took the barrel and just extended the chamber for the then new 6x47 chambering using the new 6.5x47 Lapua brass. Well the vertical came back. CCI 450 primers again, and it did close up, but again like the same barrel when a 6BR, nothing spectacular. So then i went to Lapua 308 cases, resized and shortened to fit the 6x47 chamber, but with 210 Ms in as primers, the vertical disappeared. Now that is number two example.

Number three. 30x47. Yep, using Lapua 6.5x47 cases once again, nothing but vertical at 600 yards. Four to six inches of it. Sometimes less. But groups were always more vertical than lateral. So once again off to the great 308 Lapua brass, 210Ms and many hours sizing and shortening cases, then fire forming, and my first competition group at 600 yards was a 1.6xx", mostly lateral. Went on to win the match while surrounded by some very hot shooting rigs in great calibers.
So do you think i am skeptical of the small rifle primer? You bet ya.
The story can go on as i have seen numerous other examples, not with the 6 or 30 BR, but more with the 6.5x47 based cartridges. As for Matts example with the new 308 cases, never in a thousand years will i go that route. I will leave that one to others.

Tony.
Click to expand...

From a long, long thread on primers and ignition on the 600/1000-yard forum

http://benchrest.com/showthread.php?70762-Ignition-esp.-primer-and-case-web/page4

A number of people have gone the simpler route of just opening up the flashhole. One I remember is R.G. Robinett.

FWIW
 
Last edited:
You must log in or register to reply here.
Back
Top