Home Forums Reloading Shotshells Low-pressure 20ga Loads, no 7625/4756

New old gun, new project. Looking for some resources/suggestions for reloading data for 20ga, 2 3/4in, 7/8oz, 7000-8000psi loads. Ideally would use AA hulls (supply here) but in reality whatever it takes is what it takes. The load data that had saved for this project were all 7625 or 4756 based and they've been discontinued. Did find a low pressure fed hull recipe using herco in alliant's manual. Any other suggestions?

P.s. am new to shotshell loading but benefit from a wise old mentor. His experience to date with this same task was with those discontinued powders, however.

I don't see any 7-8000 psi loads for either SR 7625 or SR 4756. And very little under 9000 psi with any suitable powder.

Why do you want to be in that range?

Michael

The quoted pressures were advised to me as a guideline for these two guns. Am open to other opinions to think on and read up on, but have to start somewhere.

Have been shooting RST Lites in a Simpson & Suhl 16 (30's vintage) and they've been fine, and could go that route again for these 20's but would like to reload my own, as have opportunity to learn from an old hand about the nuts and bolts, and hoping appropriate 20ga data will be easier to come by than 16 anyway.

The guns are a 2 3/4in VL&D/francotte eagle c1928 and later will work on the 2 1/2in lefever ds c1910 ; in both cases want to be nice to them.

The normal pressure range for 20 gauge shells is 9000-11000 psi. The factory loads stay in this range to ensure proper ignition in cold weather. The reloading data follows these same guide lines.

If you are concerned about the old guns and want to limit pressure then you can pick a hull/powder/wad/primer combination on the low side and follow the recipe exactly. For instance there is data in Alliant's manual for Herco 1200 fps load in a AA hull, W209 primer, 7/8 oz shot, same power charge: 11,300 psi with a PC20 wad, 9000 psi with a RXP20

Federal hulls generally develop lower pressure than AA's, but you still have to be very specific about wads and primers. Federal hulls do not crimp as nicely as AA's and they do not last as long. Alliant shows a single load 7/8 Herco load at 7600 psi.

You might check with Ballistics Products on the 2 1/2" loads. I have never seen any published data on 2 1/2" 20 gauge shells. Mec makes a adapter plate to allow a MEC press set up for 3" hulls to load 2 3/4" hulls. This same adapeter will allow you to load 2 1/2" hulls on a press set up for 2 3/4 ' hulls.

While I understand you interest in taking it easy on these old guns, I do not think the difference between 7000 psi and 9000 psi is going to make any difference to the guns. Either it is safe to shoot with normal loads or it is not safe to shoot at all.

Michael

Thanks for the insights and suggestions, Michael, they are welcomed. Had noted that very alliant load using Herco for 7600 psi. And you're right of course, the guns (all with fluid steel barrels) are safe to shoot or they're not. My thinking re: pressures here is more shooting them at pressures that were typical at the time of their manufacture so as to not mindlessly batter the receivers and be rebuilding them prematurely or cracking them. Thanks again, am all ears for suggestions.

Opening and closing the action is by far the biggest and also the least avoidable cause of wear and tear to a double barrel shotgun. Keep the locking surfaces clean and lubricated and don't worry about the shells.

Michael

Yeah, what he said. If I owned those two guns I wouldn't fret about beating the bushes for extra-low pressure loads.