Maker 85 grain copper
Posted: Fri Jun 18, 2021 6:51 pm
What I was after was a reduced recoil and penetration HD load. I tried a 12 ga but that wasn't reliable enough and to develop what wanted in a shotgun would have taken too much time with todays available component supply. But I know metallic handloading so that's what I fell back on. Not all of the data is here, just what I settled on.
I would have been happy with a 3" group at 50 yards, but the group was under an inch with my old eyes and a red dot sight. I called it more than good.
Maker 85 grain copper
10.3" BA barrel 1/7 twist
19.6gr ww296 w/linear compensator
Using my LabRadar unit I got my data* and it was clear which load was the best. I was going to test another powder and I need to hold myself back from doing more testing which costs $ and takes time. How much better can things get? As it stands now I'm getting ~2300 fps from the 10" barrel and accuracy is 1" @ 50 yards; much better than my very generous 3" @ 50 yard requirement for acceptance. I'm getting exactly what the cartridge is designed to do... give M4 ballistics from a much smaller firearm. But it's capable of doing much more. I'll get there eventually.
As expected the bullets slow down rapidly so are a short range load.
*Not an inexpensive unit but its a ballistics lab in a relatively small piece of gear. Could I have figured out which load was the best with a skyscreen unit? Yes, but it would have taken longer since I would have had to do the computations. But in this case the data was so clear as to be immediately discernable. What I wouldn't have gotten was the data down range that proved just how rapidly the bullets slow down (see below).
V100 is the velocity at 100 yards. Ke is kinetic energy in ft/lbs. And PF is power factor, useful only for competition. (Darn it! It didn't keep the formatting I see before posting. Nothing I can do about it.)
Stats - Average 2308.7 fps
Stats - Highest 2321.7 fps
Stats - Lowest 2294.02 fps
Stats - Ext. Spread 27.68 fps
Stats - Std. Dev 13.92 fps
Shot ID V0 V4 V15 V25 V50 V100 Ke0 Ke4 Ke15 Ke25 Ke50 Ke100 PF4 Proj. Weight Date Time
1 2322 2304 2255 2210 2088 0 1017 1001 959 921 823 0 195.84 85 05-16-2021 12:58:50
2 2294 2277 2230 2187 0 0 993 978 938 902 0 0 193.54 85 05-16-2021 12:59:36
3 2310 2294 2247 2204 0 0 1007 992 952 916 0 0 194.99 85 05-16-2021 13:00:23
Removing the linear comp' and putting the Amtac 7.62 CQB on didn't change the POI one iota. Function was fine with the linear comp' and the can.
Since the CQBm isn't a hearing safe can, it only exists to get rid of blast and reduce noise slightly I had to test the load indoors and it's fine on my ears if a bit loud. No blast effect on the eardrums. So why does the can exist? It removes blast and is very short because it extends back over the barrel, adding only a few inches to the firearm length. If I have to use these loads for their intended purpose I'm not concerned about the slight hearing loss but about more important things.
I would have been happy with a 3" group at 50 yards, but the group was under an inch with my old eyes and a red dot sight. I called it more than good.
Maker 85 grain copper
10.3" BA barrel 1/7 twist
19.6gr ww296 w/linear compensator
Using my LabRadar unit I got my data* and it was clear which load was the best. I was going to test another powder and I need to hold myself back from doing more testing which costs $ and takes time. How much better can things get? As it stands now I'm getting ~2300 fps from the 10" barrel and accuracy is 1" @ 50 yards; much better than my very generous 3" @ 50 yard requirement for acceptance. I'm getting exactly what the cartridge is designed to do... give M4 ballistics from a much smaller firearm. But it's capable of doing much more. I'll get there eventually.
As expected the bullets slow down rapidly so are a short range load.
*Not an inexpensive unit but its a ballistics lab in a relatively small piece of gear. Could I have figured out which load was the best with a skyscreen unit? Yes, but it would have taken longer since I would have had to do the computations. But in this case the data was so clear as to be immediately discernable. What I wouldn't have gotten was the data down range that proved just how rapidly the bullets slow down (see below).
V100 is the velocity at 100 yards. Ke is kinetic energy in ft/lbs. And PF is power factor, useful only for competition. (Darn it! It didn't keep the formatting I see before posting. Nothing I can do about it.)
Stats - Average 2308.7 fps
Stats - Highest 2321.7 fps
Stats - Lowest 2294.02 fps
Stats - Ext. Spread 27.68 fps
Stats - Std. Dev 13.92 fps
Shot ID V0 V4 V15 V25 V50 V100 Ke0 Ke4 Ke15 Ke25 Ke50 Ke100 PF4 Proj. Weight Date Time
1 2322 2304 2255 2210 2088 0 1017 1001 959 921 823 0 195.84 85 05-16-2021 12:58:50
2 2294 2277 2230 2187 0 0 993 978 938 902 0 0 193.54 85 05-16-2021 12:59:36
3 2310 2294 2247 2204 0 0 1007 992 952 916 0 0 194.99 85 05-16-2021 13:00:23
Removing the linear comp' and putting the Amtac 7.62 CQB on didn't change the POI one iota. Function was fine with the linear comp' and the can.
Since the CQBm isn't a hearing safe can, it only exists to get rid of blast and reduce noise slightly I had to test the load indoors and it's fine on my ears if a bit loud. No blast effect on the eardrums. So why does the can exist? It removes blast and is very short because it extends back over the barrel, adding only a few inches to the firearm length. If I have to use these loads for their intended purpose I'm not concerned about the slight hearing loss but about more important things.