jonk
05-04-2009, 09:33 AM
Figured I'd try some cast lead in my 6.5 Jap type I. I tried 2 molds. Lyman 140 gr and the Lee Midsouth 170 gr cruise missle. Both cast with WQWW+5% 50/50 solder.
First problem- the Jap die wouldn't accept the .266 Lyman bullet much less the .268 Lee. The Lee was fat enough that it actually would seat on the 'shoulder' of the seating die, without the bullet ever entering the stem. Odd, but it worked and runout didn't look bad. The Lymans I had no choice but to size down 1/1000 more as they would go into the stem and then stick there.
50/50 lube, gas check. There's the second problem; the Lee mold wouldn't hold the checks well. They were loose after sizing at .268. I'm going to have to open up the base of the mold a tad or run just the gas check portion into a .264 die, or else superglue them on. Probably the latter 2 for the short term until I get to the real fix.
Ok. So I read a thread here that 26 gr of 4895 might be a good load for these. Both bullets seated to just off the lands. Worth a shot as I had 4895 readily on hand. Results:
Lyman- nothing great. All on paper but maybe a 10" group at 100 yards. Bullets DID stabilize. No real leading.
Lee- I used a dacron fluff filler on these to help hold the gas checks on the base for the ride down the bore.
Results? The worst leading I have ever seen! After 10 rounds!
Given a good bullet fit (3/1000 over bore size) seated to the lands and a decent lube I'm forced to consider one of 2 things happened. Either despite the dacron, the gas check was falling off- quite possible considering the base of the bullet protruded well below the neck- or whatever the rifling twist rate in this gun is, it was incompatible with higher velocity heavy cast bullets much like a 6.5 Swede. Or maybe both.
Lots of scrubbing with steel wool and such and the bore is mostly clean. It's soaking for a week with Kroils to try and get under whatever is left.
Thoughts? Next time I'm going to try the other end of the spectrum with like 8 gr of Unique or Red Dot and see if the velocity theory could be the key.
First problem- the Jap die wouldn't accept the .266 Lyman bullet much less the .268 Lee. The Lee was fat enough that it actually would seat on the 'shoulder' of the seating die, without the bullet ever entering the stem. Odd, but it worked and runout didn't look bad. The Lymans I had no choice but to size down 1/1000 more as they would go into the stem and then stick there.
50/50 lube, gas check. There's the second problem; the Lee mold wouldn't hold the checks well. They were loose after sizing at .268. I'm going to have to open up the base of the mold a tad or run just the gas check portion into a .264 die, or else superglue them on. Probably the latter 2 for the short term until I get to the real fix.
Ok. So I read a thread here that 26 gr of 4895 might be a good load for these. Both bullets seated to just off the lands. Worth a shot as I had 4895 readily on hand. Results:
Lyman- nothing great. All on paper but maybe a 10" group at 100 yards. Bullets DID stabilize. No real leading.
Lee- I used a dacron fluff filler on these to help hold the gas checks on the base for the ride down the bore.
Results? The worst leading I have ever seen! After 10 rounds!
Given a good bullet fit (3/1000 over bore size) seated to the lands and a decent lube I'm forced to consider one of 2 things happened. Either despite the dacron, the gas check was falling off- quite possible considering the base of the bullet protruded well below the neck- or whatever the rifling twist rate in this gun is, it was incompatible with higher velocity heavy cast bullets much like a 6.5 Swede. Or maybe both.
Lots of scrubbing with steel wool and such and the bore is mostly clean. It's soaking for a week with Kroils to try and get under whatever is left.
Thoughts? Next time I'm going to try the other end of the spectrum with like 8 gr of Unique or Red Dot and see if the velocity theory could be the key.