I have a Uberti 1873 Cattleman in .44-40 that I hand load for. I have been shooting black powder loads for a year or so, but want to switch to smokeless for ease of maintenance. Today, I shot some loads using 8.2gr of Unique, 200gr Laser Cast bullet, with a CCI LP primer in Starline brass. There was a noticeable difference in power between some of the shots. Does anyone know what's going on?

I think I'd use titegroup

Wild A** Guess: differing crimp strength due to variations in case length. Consistent crimping makes a big difference with that sm*k*l*ss stuff.

quote:

Originally posted by buenger228:
I have a Uberti 1873 Cattleman in .44-40 that I hand load for. I have been shooting black powder loads for a year or so, but want to switch to smokeless for ease of maintenance. Today, I shot some loads using 8.2gr of Unique, 200gr Laser Cast bullet, with a CCI LP primer in Starline brass. There was a noticeable difference in power between some of the shots. Does anyone know what's going on?

Make sure you powder measure is not bridging/hanging up the powder. One round could be getting extra powder and one a light charge. Big flake powders like 800X can do this.

I didn't know that crimping had that much of an effect with smokeless. I carefully weigh each charge of powder, so I thought maybe I had a problem with the primer properly igniting the powder. It makes more sense that there would be a crimping problem because I haven't trimmed these cases in a while.

quote:

Originally posted by buenger228:
I didn't know that crimping had that much of an effect with smokeless. I carefully weigh each charge of powder, so I thought maybe I had a problem with the primer properly igniting the powder. It makes more sense that there would be a crimping problem because I haven't trimmed these cases in a while.

With a cast bullet and very hot conditions, the bullet lube can melt and run into the powder, part of the charge will become contamanated giving you a low power round. Leaving ammo in a hot car is not good.

The 44-40 round can be a bastard to load for uniform ammo. The case mouths are so thin, bullet pull &/or crimp are more important than heavier cases like 45colt. Check your expander diam. Make sure your cast bullets are the correct diam. Older brass is going to be less uniform than newer brass. I used to shoot a Henry & Uberti, gave up & went to 45colt.

I load .427" diameter bullets. I think this is the proper diameter for .44-40...

quote:

Originally posted by buenger228:
I have a Uberti 1873 Cattleman in .44-40 that I hand load for. I have been shooting black powder loads for a year or so, but want to switch to smokeless for ease of maintenance. Today, I shot some loads using 8.2gr of Unique, 200gr Laser Cast bullet, with a CCI LP primer in Starline brass. There was a noticeable difference in power between some of the shots. Does anyone know what's going on?

So, you did weigh each and every charge!!

That's good, because Unique is a powder that, while excellent, can't really be used through a powder measure. The combination of the big, fluffy, lightweight flakes and their tendency to stick together makes it impossible to throw consistent charges of the stuff through any measure I have tried it in.

I've been using it for 40 years in shotgun shells and big pistol cases, and learned this early on - and it's a PITA!! I prefer HS6 for loads that I used to use Unique for - in the .45 ACP and .45 COLT.

And yes! Crimping has a very significant influence on how well a handgun cartridge burns powder. Try to crimp them all the same-this means all cases MUST be of identical length before being loaded and crimped.....

quote:

Originally posted by buenger228:
I load .427" diameter bullets. I think this is the proper diameter for .44-40...

I used to size to .428", that could be part of your problem. Jacketed bullets run well @ .427" but I would bump to .428". Measure your expander, it's probably .426"-.427".

info hereCylinder gap can be measured with an inexpensive feeler gauge. Industry standard calls for a maximum gap of 0.012". In some cases, where bullets have lodged in barrels, measurement of the gap has revealed excessive clearance between cylinder and barrel. Throat diameter can be checked with a dial calliper. It is important to check each throat in the cylinder, as variations can exist. A cylinder throat that is too large can allow gas to escape around it before it crosses the cylinder/barrel gap - reducing pressure and destroying accuracy. Finally, the groove diameter of the barrel should be checked by ‘slugging the barrel’. This could be achieved by using a hammer on a hardwood dowel to drive a lead bullet through a well-oiled barrel. The maximum diameter of the slug will be equivalent to the barrel groove diameter. This can be measured using a vernier calliper. If the cylinder throat diameter is smaller than the barrel groove diameter, poor accuracy will result.

Anyone know off the top of their head the recommended case trim length for .44-40?

1.295

Your problem may vary well be crimping since you havn't trimmed your cases in a while and those thin necked 44-40 cases will stretch.

AS mentioned above, Unique can be a bitch to throw through a powder measure and just a couple tenth of a grain off will make a difference when your goal is 8.6 grains.

BTW,You should measure your bore (if your unsure) unless someone here can tell you the diameter. I am unsure of the Uberti but it could be .429

quote:

Originally posted by buenger228:
Anyone know off the top of their head the recommended case trim length for .44-40?

Trim to length is 1.300" Maximum length is 1.305" in my very old Lyman manual.