Help needed with a leading issue

[semtav]

You’re problem is likely coming from the throat being to big for your bullet. Either need to set the bullet out further or get a 460 diameter bullet

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That!!

[Lone_Star]

You’re problem is likely coming from the throat being to big for your bullet. Either need to set the bullet out further or get a 460 diameter bullet

I have the bullet set out far enough to engrave into the rifling about .030 now, and have tried a bullet with the same diameter but with a reduced first band with the same results.

Would a .460 diameter bullet be enough? With a fired case mouth being .462, I want to be sure I get the right size if I order a new mold.

[ian45662]

One other thing I forgot to mention. If you do decide to go the LDPE and fire formed cases like I do then you will want to put a news paper wad on top of your LDPE wad before you compress it. The wad is such a loose fit in my case that the slight amount of suction caused from the compression plug will put the wad back up slightly. Not all the time but sometimes. The news paper wad on top of the LDPE before compressing seems to fix that. Hope you find something that works for you

[art ruggiero]

try a larger diameter wad maybe .oio over fired case dial art

[martinibelgian]

You’re problem is likely coming from the throat being to big for your bullet. Either need to set the bullet out further or get a 460 diameter bullet

I have the bullet set out far enough to engrave into the rifling about .030 now, and have tried a bullet with the same diameter but with a reduced first band with the same results.

Would a .460 diameter bullet be enough? With a fired case mouth being .462, I want to be sure I get the right size if I order a new mold.

You can always size down a bigger bullet, but it's hard to 'size up'. I do question your bullet being too small from the above, though, if the case mouth fireformed measures .462, something .459 should work perfectly without any leading, assuming all fouling management being done correctly. As already suggested, I would start experimenting with wads and wad columns. If that doesn't work, get some .460 bullets to try and see if that solves the issue. Don't forget you can shoot a bore-diameter PP bullet from a 'normal' chamber without issues, and that's a .450 bullet. Same happens in a ML rifle.

[Don McDowell]

A .460 bullet might work. Chamfering the inside of the case mouth and no crimp might help with your current bullet. A 1/8 inch thick lubed felt wad might solve the problem with your current bullet and full length resized cases.
Lubing the bore prior to the first shot with bore butter might even help with your current load. But in the end I still think a larger bullet will be the best ber

[Lone_Star]

Thanks for everyone's replies.
I did not mention that one of the tests that I did early on was to shoot 10 rounds with a moderate coating of bullet lube on the exposed portion of the bullet, but it didn't make a difference. I also tried a liberal coat of Bore Butter in the barrel before the first shot.

I dug through some previous targets and found the best group was with unsized brass with the load in my first post, so I will make that load again, trying just a poly wad, and then some various different wad stacks, with enough of a taper 'crimp' to hold the bullet in the case for handling.

[Tomklinger]

Only change one thing at a time….

[craneman]

If the front of your chamber has a larger than groove diameter a fatter bullet will likely help as well as making sure you have the bullet seated in the case so a lube groove is exposed adjacent to the mouth, the theory being that some of that lube will fill that space as the rest of the bullet passes through. Not sure if that is indeed the case but doing so has helped in a few rifles with a larger diameter freebore.
Good luck!
Todd

[Lone_Star]

Today's update;
I made up a load that previously shot well using unsized fire formed cases with my .459 bullet. The only change I made to it was using a .060 poly wad on top of the powder, with a .060 veg wad on top of the poly wad. It had the same leading, but less of it.

After cleaning, I then fired 3 different 10-shot loads. They were all loaded the same - unsized brass, 60g 3f, .060 poly wad, .060 veg wad, .030 poly wad, then the bullet. This stack was done to fill space between powder and bullet, the bullet was seated out to engrave the first band. I found some .469 dia bullets that I bought, put them in the lathe and turned them down to .460, .461, and .462. Cleaning and bore-scoping after each group revealed the same results - leading in the bottom of the grooves, and some smears on the flats. Again leading, but less of it.

So...... Next will probably be trying 2f and 1 1/2f (which I have already). I will also try to locate some oversized poly wads, and some SPG Tropical lube.

[semtav]

Just a long shot but nowhere do I see case length and chamber length.

[Lone_Star]

Chamber length - 2.115
Case length - 2.095 - 2.100

[Lone_Star]

Today's update;

I tried a couple of loads today using 1 1/2f, the first was my standard load, I just swapped the 60g 3f for 58g 1 1/2f. The second load was the same powder charge with a 500g flat-nose bullet that comes out to .460 dia., both using a single .060 poly wad.

The first load will need some tuning if I use it as it did not group well, but there was much less lead left behind in the barrel; no smears, just a line in the corners of the grooves. This load was unsized brass, Rem 2 1/2 primer, 58g 1 1/2f Swiss, .060 poly wad, 540g BACO bullet at .4585 dia, slip fit in the case with about .050 compression.

The second load did real well on paper, with the same minor leading. This load was unsized brass, Rem 2 1/2 primer, 58g 1 1/2f Swiss, .060 poly wad, 500g Brooks bullet at .460 dia, slip fit in the case with about .010 compression.

I have the last black powder match of the year coming up this weekend and I will load the second of the two and give it the match test.

[Blackstone]

Clean ur barrel out very well , then prelube with bullet lube or bore butter before u shoot , shoot 4 or 5 fouling shots before your string of animals wipe with a damp patch of ur choice between shots and after ur last shot . Ur wiping solution needs to have some kind of lubricant. Don't clean between relays just wipe 1 time before your next relay . I've been doing this with good results all year , ppb's work great also , that's why they saw extensive use during the bib buff hunt .

[Kurt]

Put 10 into a snow bank and wait till the snow melts so you can find those bullets will tell you what's going on.
If no snow get some fine sawdust and use it, but snow or water will do less damage to the bullet.
A bullet wider in diameter than the groove diameter will give you finning. The larger diameter the bullet the longer the fins. If one of those Finns is longer than the rest accuracy is lost. Sort of like an uneven muzzle crown will do the same.
If you changed your powder or primers redo your load work up.
If your forearm is tight on the action and the barrel heats up it puts pressure on that barrel and it will change the impact.
Leading issue is usually a fouling control, lube quality or alloy composition as well as lead getting shaved by the chamber transition into the throat.