Loading Low Pressure Rounds - The Firearms Forum

USMCSpeedy · 11-05-2012, 08:33 PM

I'm getting ready start reloading 11x52r for by Beaumont. I have found load info for smokeless powder even thought it was originally a black powder round (yes I'm aware of what can happen and I have had the firearm checked out). I'm just wondering if anyone else here loads low pressure smokeless rounds for older firearms designed for black powder cartridges and what your result have been like. Springfield Trapdoor in 45-70 for instance.

JLA · 11-05-2012, 08:37 PM

I use IMR Trailboss for this exact purpose. Simply make up a dummy round and cut the case just beneath the bullet. use that cut off case a sa dipper for your powder and measure out 10 charges, unpacked and struck level with the top (i.e. the powder would be sitting just below the seated bullet in the case) then take and average weight of the charge and reduce it by 10%. use that as your load. Trailboss runs its best consistency at 90% load density and Ive done this very procedure with many BP firearms with UNcatasrophic results.

Good luck speedy!

myfriendis410 · 11-07-2012, 09:20 AM

There are a number of powders that will get you where you want to go with careful load workup. In the 45/70 I regularly use IMR4198 and RL7 with low pressures and decent velocities. The cases fall out of the gun and the primers are rounded, but no blackening of the brass to indicate pressures so low the case fails to seal. Do a little research and you ought to get a good starting load to work with.

11-05-2012, 08:33 PM	#1
USMCSpeedy Senior Member Join Date: Jan 2009 Location: Minnesota Posts: 631	Loading Low Pressure Rounds I'm getting ready start reloading 11x52r for by Beaumont. I have found load info for smokeless powder even thought it was originally a black powder round (yes I'm aware of what can happen and I have had the firearm checked out). I'm just wondering if anyone else here loads low pressure smokeless rounds for older firearms designed for black powder cartridges and what your result have been like. Springfield Trapdoor in 45-70 for instance. __________________ If all else fails, VOTE FROM THE ROOFTOPS Trying to reform a liberal is like trying to pick up a turd from the clean end. What this country needs is more family trees that will produce more lumber and fewer nuts! -->

11-05-2012, 08:37 PM	#2
JLA TFF Moderator/Host Join Date: Feb 2007 Location: Heart Of Texas Contributor Posts: 17,407	Re: Loading Low Pressure Rounds I use IMR Trailboss for this exact purpose. Simply make up a dummy round and cut the case just beneath the bullet. use that cut off case a sa dipper for your powder and measure out 10 charges, unpacked and struck level with the top (i.e. the powder would be sitting just below the seated bullet in the case) then take and average weight of the charge and reduce it by 10%. use that as your load. Trailboss runs its best consistency at 90% load density and Ive done this very procedure with many BP firearms with UNcatasrophic results. Good luck speedy! __________________ It takes 43 muscles to frown, 17 to smile, and 3 for proper trigger squeeze. The latest caliber or gear is no substitute for experience and skill. Rifles and cartridges don't make hits -- shooters do. Fact of life: After Monday and Tuesday, even the calendar says WTF!

11-07-2012, 09:20 AM	#3
myfriendis410 Senior Member Join Date: Mar 2011 Location: Lompoc California Posts: 552	Re: Loading Low Pressure Rounds There are a number of powders that will get you where you want to go with careful load workup. In the 45/70 I regularly use IMR4198 and RL7 with low pressures and decent velocities. The cases fall out of the gun and the primers are rounded, but no blackening of the brass to indicate pressures so low the case fails to seal. Do a little research and you ought to get a good starting load to work with. __________________ Life's too short to shoot an ugly gun.....