Light load for PCC

[tomv]

I bought some Berry's 100 gr round nose hollow base bullets to play with. I had previously taken some Atlanta Arms Steel challenge ammo apart and believe that they are using this bullet over 3.9 gr of N310 ai about 1.100" COAL. I started working down a few tenths at a time from that powder charge and ended up at 2.5 gr before my PCC failed to cycle. I'm running a Taccom upper with JP bolt and SCS buffer. To be safe I picked 2.8 gr to run and made a few hundred of them using Fed SPM primers.

 

Surprisingly, my gun cycles very positively and ejects brass 8' or so at this charge. I rested my gun and ran samples from 3.7 gr down to 2.8 gr for accuracy at 50'. 10 shot groups ranged from about 2 3/4" to a little under an inch with the best accuracy at the 2.8 gr load.

 

The 2.8 gr load chrono's at 917 fps avg with a std deviation of 22 fps, so PF = 91.7. My PCC weighs about 5 pounds and feels almost like a 22 with these loads.

 

When I talked with my friend about this he told me that he learned of an even lighter load based on a coated 124 gr bullet which came in at 84 PF. Anyone have experience with loads of this type with a heavier bullet moving at a very low velocity?

[cecil]

I shoot a Taccom 5.25" ULW barreled upper in my PCC w/Quarter Circle lower w/Blitzkrieg buffer.. … 124 gr plated bullets & 3.8gr Sport Pistol registers 129 PF .. downs falling steel with no problem.. however I plan to try some 100 gr bullets soon...

[tomv]

This load is  probably not good for falling steel but should scrape some paint off Steel Challenge targets OK.

[nickbfishn]

On 12/25/2019 at 12:19 PM, tomv said:

I bought some Berry's 100 gr round nose hollow base bullets to play with. I had previously taken some Atlanta Arms Steel challenge ammo apart and believe that they are using this bullet over 3.9 gr of N310 ai about 1.100" COAL. I started working down a few tenths at a time from that powder charge and ended up at 2.5 gr before my PCC failed to cycle. I'm running a Taccom upper with JP bolt and SCS buffer. To be safe I picked 2.8 gr to run and made a few hundred of them using Fed SPM primers.

 

Surprisingly, my gun cycles very positively and ejects brass 8' or so at this charge. I rested my gun and ran samples from 3.7 gr down to 2.8 gr for accuracy at 50'. 10 shot groups ranged from about 2 3/4" to a little under an inch with the best accuracy at the 2.8 gr load.

 

The 2.8 gr load chrono's at 917 fps avg with a std deviation of 22 fps, so PF = 91.7. My PCC weighs about 5 pounds and feels almost like a 22 with these loads.

 

When I talked with my friend about this he told me that he learned of an even lighter load based on a coated 124 gr bullet which came in at 84 PF. Anyone have experience with loads of this type with a heavier bullet moving at a very low velocity?

I’ve tried dozens of combinations, from light to heavy and The best of the bunch is almost identical to what you’ve landed on...100gr Berrys w/ 2.6g titegroup. I have a recipe for a coated 135 that is also ultra soft, but it’s just to slow. After shooting outer limits and speed option I retired it.