1st real day, Chambers .50cal flinter, 42" Getz barrel

[tommy4toes]

Let me say, first - these guns are extremely accurate when you get them right. I was quite surprised with some of the groupings, and this was with a box of Speer .490's that ranged from .484" to .492" in diameter.
I went to the range with 3 different powders: Swiss 2 and 3F, and Goex 2F. Speer .490's with an OxYoke precut pt patch soaked with LeHigh Valley lube, and Swiss 4F for the pan.
 I started out with Swiss 3 F, shooting 3 shot groups (no wiping) to be able to observe fouling, etc. 55 grs first, then 60, then 65.
The 3f Swiss didnt group very good - 4" or so at 50yds, but the fouling was very light - no problems whatsoever with a 3 shot string. I was having a few problems with my rest, and my nerves hadn't settled down yet, so I plan on re-shooting this powder next weekend.
Switched to Swiss 2F, and the group sizes started coming down to 1 1/2 - 2" with a few one holers. Fouling was still very light and manageable.
The real surprise came with the Goex. Accuracy was 1 1/2" (all in the black) at 50yds, with some light breech fouling and ignition problems with the 55gr charge. 60grs brought the group in  alittle,  but when I went to 65grs, the fouling disappeared and I ended up with a group just under an inch - a quarter covered it. Still had some ignition problems, but i suspect the vent was pretty fouled out.

All in all a pretty enlightening day, and I haven't even got got to try muzzle-cut patching yet; this was just to establish some baseline loads to work with.

t4t

[Charles/NM]

Very interesting.  So the fouling went away with heavier loads?  Is what normally happens?  Could be an indication that you've reached an  optimum load.  Hmmmm.
Charles/NM

[HWooldridge]

Maybe you reached the point where the ball upset and provided enough resistance for the charge to burn efficiently.  That also may have minimized the shot to shot variation so accuracy improved.

[olduvai george]

t4t Sir:  glad you had a successful  day  and found a good load.   now think of this concerning your ignition problem.  when the pan powder ignites it is really a very low pressure flash.  but it must throw a spark through the vent into the main charge to fire.    when the main charge ignites it in turn forces a jet of fire out of the vent and across the pan.  this jet is measured at thousands of lead units of pressure   and some very high temperature.  certainly a much higher temperature and pressure than the pan flash.  and it certainly is  coming out of the vent hole.  so the hole is perfectly open after the shot because of that jet.  you almost make what is called a shaped charge when you prime your pan.  with the frizzen down and considering the shape of the pan cavity,  your lock will fire its strongest flash at the vent somewhere between 1/3 to 2/3 full to the level of the flashhole.   most rock lock shooters  rotate the gun  with the frizzen down about 60 degrees toward the outside of the pan to stack powder there and "shape the charge"  by a quick twist of the wrist  before shooting.   ignition problems also have an inside the barrel  component that can be explored at another time.   hope this helps.  olduvai george

[tommy4toes]

thanks for the advice fellas, I will contemplate it all. Anything that'll shoot a 1" group @ 50yds is alright by me.
As far as the ignition, I only noticed problems with the Goex - maybe it's too old ? But I dont think so - I've seen people dry old wet powder and had it work fine. The only thing I can add is that the Swiss took alot less pan powder to ignite, whereas the Goex seemed to like a nearly full pan. Hmmmmmm. More stuff to think about. I'm planning on going back next weekend and trying again with the Swiss, because I like the extra velocity and lighter fouling. At least I found a good Goex load; I have 3 lbs of that stuff that i dont use in cartridges anymore. I was thinking maybe start at 50grs with the Swiss ? That and get some Goex 3F.......see what the girl really likes


t4t