What does heat do to lube? I got some leading for the first time.

[kenn]

I've been shooting Lee 200gr LSWC sized to .452 in my Sig 1911 in both lead with 45/45/10 and powder coated. Both have shot with the same accuracy at 7-10 as best I can tell and there never has been any noticeable leading and the barrel cleaned right out. Load is bullseye with 4.0 grains. Alloy is about 65% COWW and 35% SOWW.

I traveled to Houston and had a box of lead .45 above lubed with 45/45/10 and they were in the trunk all day for 2 consecutive days. Temps were in the high 90s and they were in a dark colored car in the trunk. It didn't dawn on me until I got to the range that it might be an issue (I thought I only brought PC) but I shot anyway. I'm not certain if it was stored bullet up or down as it moved around the trunk. It is very possible it was both during those two days.

The very first shot keyholed at 7.5yds. Every shot thereafter keyholed. Every single one. Though they were keyholing, they were going exactly to point of aim so I shot some more to see if I just had a few bad ones. Nope. I gave up, put it away, and shot some 9...

Fast forward to the cleaning and there was some leading that was pretty much the full length of the barrel in the grooves. It wasn't drastic but I could see it. It took a back and forth about 30-40 times with a boresnake (brass bristles) to get it out and it's now pristine clean again.

Would the heat be responsible for damaging enough so that even the very first round would keyhole? I would think if that was the case, there would have been severe leading but it came out pretty easily and seemed pretty thin.

What are your thoughts on the keyholing and mild leading? I've never had it before and shot 45/45/10 in the past.

[Ben]

What are your thoughts on the keyholing and mild leading? I've never had it before and shot 45/45/10 in the past.

Slight changes in alloy composition could result in bullets that were slightly smaller than the ones you'd fired previously. Unless you're really on your game with a micrometer monitoring batch to batch consistency of your cast bullets , you'd have never caught it in the preparation of your reloads.

Bullets that are too small will result in increased leading and possible key holing.

I have my doubts that the heat did anything at all to the 45/45/10.

[kenn]

Thanks for the feedback, Ben. I will note that every single round goes through a lee push-through sizer at .4525 (I've mic'd many and they all come out right at that) and if I push anything that feels light, I usually toss it in the cull bin without measuring as I will have generally cast 300 or so and it's not worth it to stop for just one.

[tomme boy]

Its the TL bullet design. It was stripping. I always had to do two coats to stop leading with alox. It also stopped when I stopped sizing them. The TL design is very marginal for bearing surface for the rifling to grab.

[kenn]

Its the TL bullet design. It was stripping. I always had to do two coats to stop leading with alox. It also stopped when I stopped sizing them. The TL design is very marginal for bearing surface for the rifling to grab.

Mine aren't the TL design... They are the #68 clone Lee Bullet. I tumble lubed with 45/45/10 before sizing and again after sizing so two coats.

[Dusty Bannister]

Do you suppose that being exposed to high temps, and likely still hot when shot, that would accellerate the powder burn rate and pressures? Might have been just enough to push you from no leading to light leading. LLA and the tumble lube are not particularly noted for maintaining a good seal like a beeswax lube would do. Dusty

[tomme boy]

When I said two coats, it was after sizing. I then stopped sizing altogether. This was with the TL design though. The alox is so marginal it could be anything. So if it actually keyholed at the first shot, either the bullet was too small or the bullet was stripping the lead from too much pressure.

[kenn]

I may try backing it down from 4.0 grains of bullseye to 3.7 or so and see if it makes any difference. 4.0 is by no means a large load. By the time I got around to shooting, I had moved indoors and it had been dark for an hour or so and there's no way the ammo was hot any more. I'm going to start at the beginning and reslug my barrel. I'll measure the OD of several pulls and see if maybe the FCD is too tight and crimped them to the point of reducing the diameter. After that, well... We'll see.

[canyon-ghost]

That's it! Experiment and measure a little, everybody does.

Good Luck,
Ron

[kenn]

Well, I've re-slugged my barrel. Originally I got .4515, but one of the groove "pairs" is measuring .452. I ran three slugs through and every time I got the same thing. Basically 2 pair of opposite sides at .4515 and 1 pair of opposite sides at .4520. Interestingly, the leading was only in one groove. Given my sized boolits are right at .4520 to .4525 from my push through lee sizer, I'm going to guess that the one groove that is slightly deeper is the culprit of my issues. I'm going to maybe try honing my sizer a tiny little bit to maybe .4527 or so and see if I can get it to seal up on that last groove with lubed boolits. Anything bigger and I'll have to have some throat reaming done as it's already hard to get stuff to feed.

Moral of the story is this: The boolit lube does get runny at 140 which is probably what it did in my trunk, but there wasn't a ton of powder caked on the bottom of the boolit so I don't think it was a contributor to the issue. I just think maybe my alloy as mentioned above didn't quite get all the bands to .4525 as this time is was a mix of clip on and stick on wheel weights instead of straight coww. Razor edge it seems.

[tomme boy]

Run your lead at 50/50 to soften it a little more. That will help fill the bore when fired.

[dnotarianni]

BHN of 7-10 is marginal I would go 10-12 At 4gr of Bullseye your not pushing it much at all and may not be getting obliteration in the bore causing your leading.

dave

[tomme boy]

He is talking about 7-10 yards not hardness.

[dnotarianni]

He is talking about 7-10 yards not hardness.

Me bad

[williamwaco]

Are you sure they were keyholing?

Hitting the point of aim makes me wonder if they were not keyholing but just tearing the target paper as they passed through.

see:

http://reloadingtips.com/pages/heyholes.htm

[kenn]

Thanks for the information link. I'm fairly certain it was keyholing as I was punching clean holes in the same paper target and they were nice round holes with my 9MM. The holes from the .45 were huge. With a 7 round mag, I opened about a clean 5" diameter hole in the target all in one location. It's possible, I guess, that the 45 was tearing huge holes and the 9MM wasn't. I should have kept the targets...

Are you sure they were keyholing?

Hitting the point of aim makes me wonder if they were not keyholing but just tearing the target paper as they passed through.



see:

http://reloadingtips.com/pages/heyholes.htm

[Grump]

Type of target paper can indeed make a difference at .45 ACP/200-gr boolit speeds. 9mms are just getting fast enough to zap the paper for clean holes all the time. Ordinary typing/copying paper with long cellulose fibers for strength can rip.

Now if you were seeing partial boolit nose profiles, or short parallel sides with a curved cutout to a radius much larger than boolit diameter, those indeed would be keyholes.

Depending on the usual description of "good" groups are, some people can make an old Iver Johnson with a sewer pipe barrel shoot quite well at 7 yards. It's just not far enough out to assess accuracy unless you're measuring to .05 of an inch, but many loads that look good there fall apart starting about 20 yards.

[kenn]

Back to same range... Same issue with powder coated boolits so I pulled the target and inspected carefully. Tear mark looks EXACTLY like the shape of the boolit base. Upon closer inspection, however, there is a dirty ring where it appears the boolit went through. So... tears not keyhole it seems. I did, however, get some leading in one groove which I believe to be the not-exactly-the-same diameter grooves. I'm going to try to beagle or lap to make darn certain both bands are fully .4525 which is what my lee sizer usually does when clean.

[tomme boy]

I think you may need to check the throat on the barrel. Look to see if it is a little off center or if it is a finished chamber. Somewhere on here there is a sticky about throating. Check it out and compare the pictures that are posted to your throat. It seems that a lot of the manufacturers are skipping this step as they think everyone should be shooting jacketed bullets.

[bruce381]

IMHO as a lube guy (40 years blending and formulating industrial lubes) the heat would only allow faster throw off at the muzzle.
If it worked before will work now thats my 2 cents.