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ndh87
08-26-2012, 10:43 PM
Got a chance to shoot a batch of 38spls today, they weighed out at about 163 grns and were sized to .356, just enough to go through the cyl throat on my old speed six with a little push. They were lubed with lee alox and beeswax. The bullets were flatnose with the single large squared lube groove.

loads were 38 brass with 3.7 grns of titegroup.

First six rounds hit perfectly, one ragged group from about 7 yards, and the barrel still looked clean. The next six opened up to about a 6 inch group. Ran a bore snake through the bore and the next six went back to one ragged hole.

What really has me scratching my head is that i put 10 rounds through my micro grove marlin 1894 and still got one ragged hole after 10 rounds. And that one doesnt show any leading either.

So, do i need to size .358, change my lube, both? neither?

462
08-26-2012, 11:00 PM
A .38 Special jacketed bullet is .357", so why wouldn't a .356" cast boolit lead and affect accuracy?

Leading is not necessarily easy to detect, in a powder and lube fouled barrel.

MtGun44
08-26-2012, 11:28 PM
.356 is probably too small. Probably leading and loosing accy. Try .357 or .358.

Bill

geargnasher
08-26-2012, 11:41 PM
I'm going to pop off and make some WAGs based on common issues. First, check the revolver's groove diameter with a dead-soft lead slug, check for a barrel restriction commonly called "thread choke" where the barrel screws into the frame, and ream the cylinder throats to the same or larger than full groove diameter. Size your boolits to the cylinder throats like you did before (likely you'll be using at least 357" boolits by the time you get the dimensions worked out).

I'm assuming the 1894 is .357 Magnum. I'm very surpised you didn't get a lot of leading using .356" boolits in it, most of those guns like a fatter than normal boolit, normal being in the .358" range. .359" is more common but not always necessary. The only explanation I have that it didn't lead was that the alloy was soft enough to "slug up" and obturate (seal) the bore and not allow any gas cutting (which results in leading).

I'd "slug" the rifle too with a dead-soft lead slug and long brass rod wrapped in electrical tape to see what the groove dimension is, and measure the inside of a case fired in the rifle to see how large of a boolit it will safely chamber. Remove any trace of crimp before measuring.

Gear

Wayne Smith
08-27-2012, 08:01 AM
How experienced are you detecting lead? If you are relying on a bore snake to clean you really can't tell. Get a rod and clean, white tight fitting patch. Run this patch through your bore about 5-10 times dry. What color is it?

There is no point slugging a badly leaded barrel. My brother tells me of guns coming into the shop that appear to be smooth bore. After about a week of cleaning they appear to have almost new barrels. I'm not suggesting yours is that bad, but you do not indicate that you have but much elbow grease into cleaning it, either.

44man
08-27-2012, 09:10 AM
It is a revolver guys! Throats sound too small and it will do no good to use a larger boolit. The bore needs cleaned to bare steel and slugged to see If throats are larger, then slightly harden the lead and change lube if they are. If not, the throats need reamed or lapped.
Now the rifle is different, very hard to get the same stuff to work in both guns.
Gear is right in that the boolit might have "slugged up" but that is not a good idea in the revolver. The Marlin should use a larger boolit to gain grip from the shallow rifling.
To size a boolit in throats of a revolver when the bore is larger means pressure must be very high once the boolit is in the rifling to again expand it. The problem is that pressure has gone down. Gas leakage has already taken over.

runfiverun
08-27-2012, 04:26 PM
he doesn't have any leading he is just losing accuracy and a wipedown returns it.
hmm alox..
the calcium soap is known to build up in the corners of the lands.

i'd do a quick try with another lube in the revolver before i done anything else.
and just keep on shooting the marlin keeping an eye on things.

the measurements/sizer whatever might just be off a bit.

ndh87
08-27-2012, 08:48 PM
ordered up a .358 sizing die. we'll see how that turns out

44man
08-28-2012, 09:31 AM
he doesn't have any leading he is just losing accuracy and a wipedown returns it.
hmm alox..
the calcium soap is known to build up in the corners of the lands.

i'd do a quick try with another lube in the revolver before i done anything else.
and just keep on shooting the marlin keeping an eye on things.

the measurements/sizer whatever might just be off a bit.
Just maybe, my downfall has always been Alox! [smilie=s:

popper
08-28-2012, 01:23 PM
lee alox and beeswax. I've never had a dry bore snake remove anything but lube/powder residue and maybe a little grey dust. Cool down time between reload of the groups? My marlin will do that on long strings, using recluse lube.