329pd Oregon Trail tears and travails

[totaldla]

I tried high velocity (with slow powder) and plinker (with fast powder) loads today, built from .429" and .430" sized Oregon Trail 240gr lswc bevel base(originally .431" until resized using Lee sizers).

The 20gr Ramshot Enforcer load runs right at 1200fps on a warm day. I shot 6, inspected, cleaned the bore and repeat. The .429" leaded more than the .430", but neither leaded enough to keyhole after two cylinders of shooting. Poor accuracy. Not keyholing, but a shotgun 25yd pattern with both with the edge going to the .430" stuff.

Next up was the 6.5gr Hodgdon Clays load which runs a little over 900fps. Again, it appeared as though the .429" leaded more, but the difference wasn't that great. I shot 30 .429"-sized in a row, and the barrel "seasoned" and settled down. No keyholing. Point of impact shifted a lot at 25yds. Accuracy was better than the 1200fps load but not stellar.

I'm going to try the polystyrene pads next. Also some very stout loads with W296 and LilGun. And maybe some Alox-lubed bullets.

I'm dreaming that I'll conquer those Oregon Trail bullets in my 329pd.

I ended up doing a lot of this today

 

[That'll Do]

For what it's worth, I'd try shooting the Oregon Trail bullets as is, without sizing them down to .429" and .430".

I'm not surprised the .429 loads leaded more. Cast bullets usually should be at least .001" larger than jacketed.

 

[totaldla]

For what it's worth, I'd try shooting the Oregon Trail bullets as is, without sizing them down to .429" and .430".

I'm not surprised the .429 loads leaded more. Cast bullets usually should be at least .001" larger than jacketed.

I tried shooting them unsized and I got lots of leading (see sigline). My cylinder throats are a hair over .429. So I decided to try sizing them smaller in hopes of finding what my revolver likes.

 

[P-990]

I'd bet your cylinder throats need to be polished out to about .430-.431". If the bullets leaded your barrel unsized, I'm guessing the throats are swaging the bullets down too small before they hit the forcing cone and barrel.

I used to run Oregon Trail 240gr SWC out of the box through my 629. It would eat them over a full-dose of 296 with no leading issues. I still prefer XTPs for full-bore loads, but I haven't tried any LBTs yet.

 

[totaldla]

I'd bet your cylinder throats need to be polished out to about .430-.431". If the bullets leaded your barrel unsized, I'm guessing the throats are swaging the bullets down too small before they hit the forcing cone and barrel.

I used to run Oregon Trail 240gr SWC out of the box through my 629. It would eat them over a full-dose of 296 with no leading issues. I still prefer XTPs for full-bore loads, but I haven't tried any LBTs yet.

I agree with your theory, and as UncleNick pointed out bullet hardness (OTs tend to be very hard) is making the problem worse. I'm not sure, as I've never asked a gunsmith, but I don't believe the titanium cylinder can be machined.

The Cast Performance LBT-style bullets I've tried work very well out of my 329pd.

 

[HiBC]

I don't know anything about 329's.I have some experience with Lasercast in my Super Blackhawk,and hundreds of pounds of experience with plain old wheelweight bullets.I bored the gascheck out of a Lyman 240 gr or so Kieth because I was tired of gaschecks.With as much Hogdon H110 as the book said I could use,I got zero leading.Leading has just never been an issue.
I do agree that any gas flow around the bullet is a problem.Lasercasts,quite hard,may not bump up so well.If your cyl throates are smaller than your bore,HmmmmSunnen makes a good hone machine and some folks know how to use them.
What you might try is a softer bullet,and maybe,lose the bevel base(I don't knw why,but???).You also might try Oregon Trail's gas checked line.
OT is a good outfit,but cast bullets are some about what that one gun likes.
Another place you may find progress is bullet lubes,but the OT's come pre-lubed.
It is also true that sizing a bullet can decrease accuracy.Miimal "rounding" as they are lubed is good