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ray ott
04-26-2009, 10:34 AM
Handloader magazine article appeared to accept that everybody knew about the jump in chamber pressure with gas checks. Been loading 40 yrs,never ran into info. Any help out there?

Buckshot
04-27-2009, 02:53 AM
Handloader magazine article appeared to accept that everybody knew about the jump in chamber pressure with gas checks. Been loading 40 yrs,never ran into info. Any help out there?

............Did the article give examples of pressures with and wothout? As a rule cast loads aren't loaded in the "Death Wish" area of pressures but then again, cast IS loaded in many old black powder transitional firearms eg: Trapdoors, Sniders, etc) . So there even conservative loads 'might' be close or possibly even a bit over what they should be fed.

Tell ya the truth, if I had a PB and GC version of the same slug I surely wold have loaded either with eh same charge and not thought a thing about it. Gee, now I have something else to worry about, heh, heh!

...............Buckshot

Lloyd Smale
04-27-2009, 07:18 AM
never noticed it myself. But then i usually dont load to the ragged edge. I think it just wasnt the month for the 270vs3006 article and the author wanted to get paid!

Bret4207
04-27-2009, 07:34 AM
If you check the original statement and Brian Pearces follow up statement he qualifies what he meant. IIRC it was that a GC can give higher pressures in some loads versus PB. If you think about it the GC SHOULD give higher pressures since part of it's job is that of a seal. No big deal really, unless you're running PB loads at the outer limits of good judgment and then switch to a GC with no load change and we're all experienced enough to know you wouldn't do that, right?

dakotashooter2
04-27-2009, 09:58 AM
It make sense that there might be a slight increase in pressure but I always understood that in a condom bullet it was the bearing surface tension of the copper that caused pressures higher than lead. With a gas check the actual copper bearing surface would be very minimal.

1hole
04-29-2009, 04:11 PM
"With a gas check the actual copper bearing surface would be very minimal. "

Roger that.

The GC will perfectly match bore diameter after it has entered the rifling its own length of about 1/16th inch. AND the bullet will have just laid down a layer of lube on the bore, so I just can't get too worked-up over an increase in chamber pressure any magazine writer suggests a GC might possibly cause!