Lee c312-155-2r results

[Wisest.fool]

recently i started casting bullets for rifles. I had good results. i posted them here: http://castboolits.gunloads.com/show...60#post4885760

Since i good results from that test I repeated it with a lighter bullet. the lee C312-155-2r. I chose this bullet because budzilla gave me some to try. I wanted to push a cast rifle bullet faster than 2300fps. I thought i could find the failure point of powdercoating or at least where it starts to lead. spoiler alert: they didn't.

so the process was the same the testing equipment was the same to save you all the time of reading the other post i will repeat some of it.

Rifle - Ruger precision rifle 308 win
bullet - C312-155-2R - COWW + 2% tin - water dropped - gas checked - powdercoated with smokes powder. sized down to .309
case - FC 308 win
Primer - CCI LRP
Powder - IMR 4895
range - 50M
Lead bullets go down the pipe quicker than jacketed based on my last test. so load data was started 10% lower than min load.

lead bullets after gas check and PC were roughly 160gn.

Bullets were sorted into groups of similar weights

Results:
37.5 gn IMR 4895 - 2225 FPS less than 1 MOA if you exclude 1 flier
39.5 gn IMR 4895 - 2426 FPS 1 MOA
41 gn IMR 4895 - 2520 FPS 1.25 MOA if you exclude 1 flier

after 41gn groups kept opening up farther and farther.

Pictures or it didn't happen:
https://drive.google.com/file/d/1E1a...ew?usp=sharing
https://drive.google.com/file/d/1EF9...ew?usp=sharing
https://drive.google.com/file/d/1EHx...ew?usp=sharing


Then i did the same test again changing two variables: powder and bullet

new powder : H4895 since i ran out of IMR 4895 and my store couldn't get any more thank you COVID
new Bullet: after trying bullets from Budzillas mold lee C312-155-2R i bought my own mold CTL312-160-2R. This made the bullets come out roughly 165gn which is perfect IMHO. powdercoated raspberry red. Thanks Budzilla for the lipstick colored bullets. (i go the powdercoating from him)

results:

best group 37gn H4895 forgot chrono or i would have a velocity. less than 1 MOA maybe .85 MOA first three went through the same hole next two were off by 1/4 inch

38 gn and 39 gn would be close to 1 MOA if you got rid of one flier. after that groups opened up.

pictures or it didn't happen:
https://drive.google.com/file/d/1EKo...ew?usp=sharing

so yeah loving this cast rifle bullet thing. way more accurate than i thought it would be. no leading so far up to 2700 fps. uses slightly less powder than FMJ.

Thought i would put this up here for others to see. Hope it helps

[Larry Gibson]

As to accuracy you might test those bullets and load [the last 37 gr H4895 load} at longer range than 50m as it appears you have longer distance at your range. That Ruger PRC should not have a "sweet spot" like that load in and amongst the other groups. All the groups should be relatively the same size give the load spectrum. The other groups around that load are telling you something.