Lee 312-155 for the 300 Black out

[Rockchucker]

Does anyone shoot this bullet sub sonic or super? I've ordered the mold along with some gas checks and was wondering if it was to light to cycle the action with around 1000 fps. Next question, Finding load data for the 300 isn't published in the manuals I have, so finding a trusted load seems very difficult. I have 2400,H110,H4198, IMR4198,imr4227 powders. I also have some Hornady 208 gr. A max bullets thats better suited for subsonic but again finding trusted load data is hard to find.

[fecmech]

I use that bullet in a 30-30 bolt action savage 340 without the gas chk. I'm currently running 8 grs of Alliant Steel(to use it up) which gives me 1300 fps and sub 2 moa@100 yds. Due to a somewhat wonky throat on this rifle it's the only bullet I can use pb'd without throat lead. I'm not into the BO thing, but if it helps just about any shotgun powder in the 8 gr range gives 1200-1300 fps with that bullet in the 30-30 cartridge.

[emorris]

You may be able to keep it around 1000fps and still cycle your action with accurate 1680 powder, but it depends on your gas system.

[petroid]

for the 312-155 start at 14gr H110 or Lil Gun. With 4198 start at 16gr. It will be too light to cycle the action at subsonic velocity. For the 208 Amax subsonic start at 11gr of H110 or Lil Gun and work down. With the 4198 start at 12gr and work down

[2wheelDuke]

I don't think you'll be able to keep that one subsonic without playing around with the gas port and/or the recoil spring. The recoil spring is pretty easy to change out to try it.

[Rockchucker]

Thanks for all the info Guys, I did find some loading data inside the die set I have. I must have over looked it. I look forward to working up or down some loads with this gun and have loaded some A max 208 grain bullets with 11.2 grains of H 4198 to take to the range. They probably won't cycle thru but I have to start somewhere and pretty sure I'll have to make some adjustments on the gun. Thanks again.

[BT8850]

I have loaded this boolit, powdercoated with a hornady gas check sized .311 supersonic using lil' gun and it shoots well in 10.5" AR. Assuming you are loading for an AR, I've found that this boolit needed to be loaded short to keep from getting the nose tight going into the chamber, 2.000" OAL and shorter has worked for me with standard metal mags and p mags. YMMV. Also, hogdons website has the reloading data center for free and has 29 300blk loads with bullets from 110g to 230g, check it out. Stay safe and good luck!

[Jared]

I have to load them fairly short, 1.965" IIRC,the nose is .305" and can cause problems clambering if seated further out. Accuracy so for has been fair but not great. More testing is in order after deer season.