44 mag Henry .432 vs .431 with AA No. 9 load vs SR-4756 Question??

[10mm_Shooter]

Hi All,

I have been chasing a small leading issue with my Henry .44 BB with 20 inch barrel. Initially I was running a 240 LRN-FP at .430 and was getting a good bit of leading in the first 1-2 inches in front of the chamber, rest of the bore was perfectly clean. Also I was running a Green Dot load at only 1075 fps across the chrony.

So I was a little small in diameter and a bit lite on horsepower

So I have gone to .431 sized and cranked up the power, with the same 240 LRN bullet at .431 (13 BHN alloy)
I ran 16.2 grs of AA No.9 for 1442 fps across the chrony
I ran 9.4 grs of SR-4756 for 1190 fps across the chrony
well these loads almost completely eliminated the leading, its to the point now that it really takes a very close inspection to notice the just a hint of leading in that 1-2 in area forward of the chamber.

So I've got a good mold and have sized some 240g LRN-FP at .432 I would like to get the AA No 9 load down to 14-15 grains, I'm guessing that should get me to 1200-1300 ish fps ?? Should I have any concerns running a .432 sized bullet in my .44 Henry any risk of pressure spikes, that is why I was sticking with a slow powder(trying to avoid any spikes that might occur with a faster powder)

I'm looking for about 1200 fps for a good velocity with .432 bullets and No.9 is my preferred powder, this should have enough punch to seal the bore and finally put to rest any leading issues.

thanks for the input

 

[Walkalong]

.432 bullets won't be a problem. My Winchester 94 grooves were over .430 as well. Bigger bullets were better. I used Blue Dot for mid-range loads in it.

AA #9 should work well as long as you don't go too light. SR4756 is too position sensitive for me, and I would not consider using it for this application.

 

[10mm_Shooter]

Range report for Sat Dec 13th.

We have success, with the new mold and sized to .432 my Henry was flawless today, I ran 100 rounds through it today and the barrel is absolutely pristine no leading, no leading

Running the .432 sized bullets was definitely the trick for it.

I chronographed two new loads today both with same 240 gr .432 sized LRN, 15.0 grs of AA#9 runs 1330 fps, 34.15 SD and 153 ES(ouch) @ 40 degrees ambient, 950 ft/lbs of energy, brass ejects and still drops in a .44 case gauge, primers show no flattening at all. Charge is so lite that brass has signs of blow by from the brass not fully sealing the chamber,(yes I know AA9 like to a full charge hence the high ES). Next trip I'll go up to 15.8 grains of AA#9....should bring me in at 1400fps then

Next was 11 grs of SR-4756, 1320 fps, 16 SD, 69 ES @ 40 degrees ambient, primers show no flattening at all, brass ejects and still drops in a .44 case gauge. This load is definitely a keeper.

I'll be checking for accuracy on the next range trip, all I had time for today was to run them across the chronograph.