BS

I shot some powder today at 100, using the 410s and sub bases.

3 shot groups

90 FFF 2 9/16"
100FF 7" horizontal string?

Only thing different that I did with the FF was wipe the barrel with lube after loading and reseat the bullet.

I clean the barrel with windex, then two dry patches, then a lubed patch of Bore Butter, fire a cap and load.

I am going to reshoot the FF with no lube afterwards, and some dry ones.

I did find some power belts 295s, 348s and some 405s that I will have to try.

cayugad

That's some very respectable shooting .... sounds like the sub bases do make a difference. I think I will order some of them.

BS

I also have some sabots that I am going to cut the pedals off and try them under some flat base bullets, might even punch out some heavy 1/2" dia. cardboard and try that under a few.

Tahquamenon

I'm also going to try some of the MMP sub bases with conical and sabot's.

Always looking for something else to tinker with.

Like I have enough time to fool with everything I have thus far!

Roskoe

You might try some Winchester AA (pink) 28 guage shotgun wads - with the petals cut off - for this application. I understand Toby Bridges used these with some success in conjunction with flat base bullets. May have been the idea for the MMP sub-base, if I recall correctly.

zac76156

Sub bases will help some by forming a better gas seal, but traditional blackpowder is extremely inefficient. The reason you get more unburned powder with the higher loads is because the powder takes up more of the bore volumetrically, thus some of the charge is farther away from the ignition source and doesn't get burned. Its really nothing to worry about, just realize that the more BP the more inefficient it becomes. The guys shooting 150gr of BP really crack me up since only about 2/3 of that load is getting burned, the rest is contributed to the ejecta and only causes the gun to recoil harder with very little increase in velocity vs the 90-100 gr load.

BTW, If your using sabots instead of powerbelts, I highly recommend MMP sabots. Just throw away whatever plastic crap comes with the bullets and use theres. They are by far the strongest on the market and at 80-100 gr. BP you shouldn't need a subbase

BS

Roskoe, my brother just had a case of 28 ga. wads given to him. so I will give some a try in my 54. They do fit nicely!

zac76156 the sub bases are not used for there gas seal, but to keep preasure from blowing away the base of the bullet.

>>>>>>>>>>>>&g t;>>>>>>>>>>>> >>>>>>>>

Here is a test that I did with my GM 27" 54cal. back in 1988.

All shot with Goex FFF and .535RB

90. 1594
100 1642
110 1740
120 1808
130 1867
140 1916

Also:

I was looking for a load to shoot saboted Hornady 44x 265grain in my 50 Kodiak. 28" bbl.
Goex powder.

160 FF 1820
170 FF 1890
180 FF 1890

150 FFF 1900

I wish I would have clocked the lighter loads, but you can see were the FF quits gaining.

Roskoe

BS - there are several varieties of 28 guage wads, as I found out the hard way. The stiff red AA wads are fatter than the flimsy pink ones - and the pink ones are about the right size for a .50 caliber. I don't own a .54, but maybe the red ones will work in that caliber. You couldn't get them down a .50 barrel with a mallet! Roskoe

BS

Mine are white Remington, and they just fit a 54 nicely. But I do have a mallet, Thanks Roskoe!