Leading in 45ACP chamber

[16in50calNavalRifle]

I've got general leading woes in all three handguns that have seen my lead reloads (Model 66, XD 9mm, Springfield 1911), a sort of "wash" of lead particles in the grooves mostly. But I am hoping that is a basic question of bullet fit, and will be slugging my bores and cylinder throats very soon to help with that. I think I understand the basics of pressures and expansion to seal the bore, and my charges are not the problem.

But one puzzler: I am seeing what I am pretty sure is leading in the far end of the chamber in my 1911. It shows up as a fairly heavy grit deposit when I shine the borelight from the muzzle end. And did not appear to be reduced one bit by my laborious cleaning (dry brush, old brush wrapped with Chore Boy, old brush wrapped with bronze wool). I think I even dry-brushed the chamber with a shotgun brush that had a tight fit.

Springfield Mil-Spec 1911, stock barrel, MBC 200 grain SWC over 5.4 grains of HP38/W231, loaded to an OAL of 1.245. Shoots just fine, accuracy seems OK, as I said, annoying light wash of lead in the grooves.

But leading in the chamber? What sayeth the tribe?

 

[LiveLife]

You may be still getting some gas cutting/bullet base erosion as the base of the bullet is leaving the case neck and high pressure gas is leaking around the case neck rim/chamber.

For .452" diameter bullet, I use .472 taper crimp (or most that the chamber will allow) and use the longest OAL that will feed/chamber reliably from the magazine. The longer OAL allows the bearing surface of the bullet to engage the rifling sooner and build chamber pressure faster to deform the bullet base and reduce gas leakage.

Even for my tight chambered Sig 1911 barrel with very close start of rifling, I do get light smearing right at the chamber end of the barrel, but the smearing comes out with a few strokes of old copper bore brush wrapped with copper scrubber (Choreboy). Also, MBC makes 200 gr SWC in softer 12 BHN (Bullseye #1) if you are currently using 18 BHN IDP #1 bullet that should help deform the bullet faster.

 

[340PD]

I had the same issues with lead bullets. Revolver or auto regardless of hardness of bullet I could never find a combo of lead/powder that did not require scrubbing some lead out of the system. Switched to plated bullets and all my problems went away. Upcharge cost was well worth it to me.

 

[16in50calNavalRifle]

340PD - understand that reaction; in my case, at least for 9mm, FMJ is available at a fairly modest premium over lead (Precision Delta), so I've already decided to do a mix in that caliber, as I seek a recipe with minimal leading. 45ACP is another matter, but I'm on the lookout for deals on FMJ there, too. For 38 special I figure I'll stay with lead and make it work. Slugging my guns should help me with my efforts to reduce leading.

bds - funny about the OAL - thanks in part to your very informative posts in this forum, I was thinking about that very issue (max functional OAL to minimize gases leaking around the base as the bullet enters the bore) as I decided on an OAL. For my initial loadings I decided to go with 1.245, even though I had found max to be 1.265 with the "plunk/cycle" testing - mostly so that the inevitable variation in seating depth, round to round, would still leave me with "headroom" within the max OAL. I will try going to 1.255, cutting it closer to max, but still with some room for variation.

Actually this has all been with the MBC Bullseye #1, BHN 12 45s, so going softer is not an option.

I'm rather discouraged with the smearing in the rifling (which I believe indicates a bullet/bore fit problem, and is present in all three handguns) - not only does it suggest I might have 3/3 non-standard bores, but even with every trick in the book and lots of elbow grease, I haven't been able to completely clean it out. As a practical matter there's just no way I'm going to use ammo that gives me a 1:1 ratio of shooting/cleaning time, so I really have to solve this leading problem if I'm going to reload with anything other than FMJ.

 

[Walkalong]

Another thing that can happen is squeezing bullets undersized when loading. Over sizing and under expanding can leave an inner diameter in the case that squeezes bullets down too much. The FCD can do it sometimes as well.

 

[LiveLife]

Good point. I do not use FCD for lead reloads to eliminate any post-sizing of the bullet diameter.

If you are using 12 BHN bullet then OAL and powder charge is what you have to work with. If you determined 1.265" to be the max OAL, I would use the longest OAL that would feed/chamber reliably from the magazine to minimize gas leakage. Due to the close start of rifling in the Sig 1911 barrel, I have to keep my OAL of the SWC bullet to 1.245" but my M&P45 will take OAL out to 1.270".

The amount of smearing I get is very minimal as 3-4 strokes with copper strand wrapped bore brush will clean the barrel and this is with the lighter 5.0 gr of W231/HP-38 using both 12/18 BHN bullets. The same loads in my friend's Kimbers will leave the barrels absolutely clean.

Out of curiosity, since you are using the softer 12 BHN bullet, have you tried lower charges of W231/HP-38? Like 5.0-5.2 gr?

 

[kelbro]

Flare a case a little more than normal and use it to scrape the chamber clean.

 

[Striker Fired]

I now use a Foul Out system and it takes very little work to clean my barrels.I just put the rod in the bore with the solvent and plug it in.20min later there is no lead anywhere in the bore,even in any pits or rough areas from the factory.

 

[16in50calNavalRifle]

Walkalong - yes, I will look closely at the setting on my expander die. I am sure I set it to the minimum that holds the bullet upright, as I've read about prolonging case life by expanding the minimum amount. As for sizing, for all my handgun brass I just use the standard die setting - should I look at backing out the sizer die a smidge?

I check the case mouth and generally have it at .472, and I don't use the FCD for lead bullets. But I am going to check the diameter at the case mouth very carefully when I do my next test loads.

kelbro - good idea ..... I've been meaning to create a scraper with .357 brass for my revolver cylinders, hadn't thought of that for 45. Tonight I was going to swab the chamber and bore with Kroil, let is soak overnight, then go after it tomorrow hard with Choreboy and bronze wool.

bds - yes, I did the usual work-up approach, had some loads with 4.8 and 5.0 HP38 also. I also tried a few loadings of Trail Boss and Silhouette. One problem with the 1911 at the indoor range - it's just too much to disassemble it and get a really close look at the bore and esp. the chamber after every loading is shot. So I snake it once for residue and use a bore-light with my reading glasses, and get a pretty decent look, but not as close as in the garage at the bench with the magnifying headset and the work light. With so many different loadings, it can be confusing to identify the culprit with something like leading (or the culprits).

I don't recall seeing the chamber leading before, but not sure if I looked for it. Only solution is to get the bore/chamber squeaky clean, lead-free, then try some longer-OAL, smaller charge loads, as well as my tentative standard load, checking for leading after each one.

 

[16in50calNavalRifle]

Striker Fired, those electronic cleaners have a certain appeal. I may go that route eventually. First I want to see what I can do with my reloading. It's a good learning experience to try and fix this problem by tweaking the ammo I make. (not purely fun, but ....... a learning experience)

 

[Walkalong]

Walkalong - yes, I will look closely at the setting on my expander die. I am sure I set it to the minimum that holds the bullet upright, as I've read about prolonging case life by expanding the minimum amount. As for sizing, for all my handgun brass I just use the standard die setting - should I look at backing out the sizer die a smidge?

You have the expander adjusted just fine. The only way to help is to get a larger diameter expander. Same with sizing, since .45 ACP is a straight walled case, adjusting the sizer up won't help, you would nee a bigger sizer.