I just picked up a Colt New Service 7 1/2" 38 W.C.F. (1907). The bore is excellent and the mechanicals and timing seem spot on.
I have Lee dies, Starline cases, and 500 180 gr cast bullets coming by Friday, 11-28-2014.
Powders on hand are Bullseye, Unique, 4756, 800X, 2400, Lil Gun, and H-110, I prefer to use one of these rather find another.
In deference to the 107 year-old steel and internals, I have no desire to hot rod the fine old Colt.
So, can anyone suggest an accurate mid-range load for shooting at 10 yards to 25 yards? also, any reloading tips I should know. Mike Venturino mentioned a problem with shoulders moving forward. Has this happened to anyone?
Thanks ahead of time.

Sizing die dimensions and chamber dimensions are critical for good results with this cartridge. Factory cases have a long neck to allow the factory crimp behind the seated bullet. When fired the neck becomes much shorter and resizing should keep it there. Careful sizing is needed to have decent case life...the case should headspace on the shoulder or case separations will plague you. Oversize chambers will also shorten case life.

I recommend using milder loads of the faster powders, no slower than X-800. Not just for the limited strength of the old pistol, but to extend case life. Then of course there is always holy black.....


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Funny, I just got back from the range shooting my 38-40 about 30 minutes ago. I shoot 180 grain lead bullets over 7 grains of Unique. No need to go hotter although the case capacity is certainly there. Yes, the shoulders will move as all factory loads I have seen are way shorter than any chamber I have or have cut. Here is what you get; no problem though. Good thing is that the Lee dies I use do not push the shoulder back so no problem there. I use Starline 44-40 brass mostly; why? Much easier to get and might give a thicker neck. Anyway, you do not know you are sizing it down anyway. Those slow powders you mention will need a case full of it to work right and that might not be what you want. Plenty of case room for black powder too. I have never had any case life problems with thousands of shots over the past 25 years. In 2 rifles and 3 revolvers. Not enough pressure to stretch a case.
Here, fired in Colt SAA, 38-40:

Thanks for your comments. I got my buulets (180 gr LFN) from Crown Bullets quickly. Ditto for the Starline brass and Lee dies from Midway so I loaded up three different loads. All shots at 13 long paces from a makeshift rest and firing west into the setting sun which made the front sight difficult to see.
1.) 6.1 gr/Unique/180 gr LFN/Federal 150: Poor accuracy and lots of unburned powder, even though I used a medium crimp. I will try again using your load of 7 gr Unique and see what happens.
2.) 6.2 gr/IMR 4756/180 gr LFN/Federal 150: Accurate-@2 1/2", although a buckaroo at the next position shooting a .40 S&W said "Oops, I accidentally fired two at your target".
3.) 6.8 gr/800X/180 gr LFN/Federal 150: 6 shots at 2 1/2+".
All in all, I was happy with the way the old Colt shot.
Yes, the shoulders did blow forward as yours did. However, the fired cases all reentered the charge holes easily and bullets would not reenter the fired cases, which should indicate decent brass strength and low pressure loads, which I will stick with.
I'll keep you posted but a cold, cold front is set to visit Sunday night so I may not get any more shooting trials for awhile.
Thanks for your comments.

Yeah, cold here too; I use Unique because I have a ton of it; not saying it is the best powder; it is just what I use for cowboy shooting and I have the old stuff that smokes like black powder. I don't get much unburned powder though. Starline brass is very thick so it won't expand too much, as you have found.

I've used various powders in my .38-40 Blackhawk, but plain old Unique has always worked best for me. The .38-40 was never intended to be a Magnum...for that sort of use, I use my Model 57 Smith.

For good accuracy, easy fired case ejection, and good brass life, I find Unique to be just the ticket.

I tried 6.8 gr Unique for a starter. Accurate but lots of unburned powder. I also tried 6.8 gr 800X. Also accurate but more unburned powder and the loads chronographed between 449 fps and 675 fps. I think the Federal 150 primer just fluffed the powder out of the case. I used a medium/light crimp. I think I'll step up to 8.5 gr of 800X and see what happens.

Both of my 38/40's are customs so have throats cut at .4015" and rebored barrels to suit. I bought a bunch of bullets from Montana Bullet Works (sadly now out of business). Their 180 gr RFP (RCBS 82306) at BNH 15 sized at .401". I use 6.5 gr of TiteGroup in Starline brass under said bullet. Shoot great in both pieces, a Smith N-Frame and an old Ruger Flattop 357 conversion.