Originally Posted by
idahoron
The reason I don't use T7 was etched in my brain years ago. I did a lot of testing on the P and the T7. At that time I was just starting to paper patched bullets. Up to then I was using pyrodex RS. My 45 was hang firing real bad so I tried the P so it would settle into the snail better and that worked. This day I was shooting my 50. I was out at the range and a buddy of mine was there to shoot his white mountain carbine 50. I was shooting 80 grains of P and the T7 I don't remember the load, But I worked up the grains on the T7 so I had the same FPS. I think I used less T7 to get to where the P was but I don't remember now.
T7-2f is about 10% hotter than the Pyros and T7-3f is listed as 15% - but I also know or think I know why it didn't work for you. T7 is to hot for your paper patching probably. I mean physically to hot like probably burns right through your paper. I learned a long time ago it actually melts the bottom of a lead bullet - leaving lead all the way up the bore. Even shooting reduced 60 grain loads with a Round Ball I have to use a lubed wad or I will burn right through the patch....
Anyway, my groups showed a real liking for the P and I was done testing. In my testing on my rifle with the paper patched bullets, I found that if I went much over 1300 FPS my 460 gr bullets were not grouping reliably. So staying in that 1300 FPS range was the target.
From my Stainless LRH barrel I found that I needed to use 90 grains to get a really tight group with the 460's but that was 1500 fps - with a shot card under the bullet.
My buddy wanted to speed test the white mountain carbine. He was not familiar with the T7 and loaded 90 grains, the same as he used of RS. He touched it off and the stock cracked.
Now that stock cracking may have been a fluke. I know that he is not the kind of guy to over tighten the lock screw. His velocity with that short barrel was 1400 if I remember right.
Between that and the fact that the T7 didn't accomplish the same groups as the P did at the same velocity was the reason I stayed with the P.
Now since that first try with the T7 I did end up hardening my lead a bit. I was using pure and now I am using lead that is between 6 and 7 BHN. I do wonder how that would affect the T7 groups.
The last thing I do remember between the two was the "crud" ring left by the T7.
Now that is odd - most of us shooting caps do not get the 'crud ring' I mean I shoot an entire Rondy even using T7 and never patch once. But then again I do not have any petroleum of Teflon products in the bore. T7 will fry both and create a hard ring just under the bullet.
I do remember that being another factor with my paper patched bullets. Yes the P does have a crud ring but I can work with it.
When I shoot T7 with shot gun primers - I do get the ring the primers are just to hot. But a Windex patch walks right through without any problems at all in fact as long as the Windex patch remain somewhat damp I just the same patch over and over.
But now with your post and my mind bringing old information - I really think I do know why you do not use T7 with soft lead and paper patch.... I really wonder though if a shot card on top of the powder and between you paper and bullet would give you better performance.
Question... with a paper patch does the bullet itself ever touch the bore or does it ride all the way out of the bore on the paper like a cloth patch?
I wonder if I can find a picture of one my 460 targets... I will look
Got it
Ballistic Sheet
