Oversized Bear Creek .40 180s

[ParaLarry]

I just received 5k of Bear Creek .40 180s; 3k were in watersoaked boxes so I transferred them to dry boxes.
I was almost out of my old 180s so I started in on one of the new boxes; after running 100 (then add primers, sit down to case gauge) I found they would not 'plop' into my case gauge. They would stop with about 1/8 showing and then would fall in with a little nudge.
My last three .40 guns have been built by Will O'Hara and each one has a Dillon case gauge reamed by Will to match his finished chamber, so the gauges are reamed for long loads at 1.180.

I was concerned and miked a random sample of 20 or so and they all were somewhat over .401, sometimes as much as .4015.
I went back to the old unfinished box and miked 20 or so and they were all right at .401; finished loading those and they all 'plop' into the gauge with no problem.

I took the 100 new 'fat' rounds to an indoor range, they all chambered and fired with no problem, but they definitely 'felt' hotter.
(I'm using 4.3 grs Titegroup at 1.180 for years)
I haven't had a chance to chrono and it may be a week or so before I get a chance.

Has anybody else received recent Bear Creek 180s and can you check the diameters?

Is there a possible future problem in running a lot of slightly oversized bullets?

Any other danger from oversized bullets to watch out for?

Before, no 'plop':


After, with a nudge:

[rsrocket1]

Did you "paint" the cartridges with a magic marker to see where it hangs up?
Do you taper crimp at all, even to close the flair of the case? Maybe you need to screw the crimp down by a fraction of a turn to just barely turn the case mouth in a little more.

[CalTeacher]

I have about 10k of those. I'll check a few tonight, but my calipers only read to the thousandths. The simplest solution to this problem is to buy a Lee .401 sizing die and run them through I they're consistently too large. The die is cheap and sizing them is extremely fast.

[thenodnarb]

1/2 thousandth in bullet diameter is not something I would worry about. What is concerning is that you have a chamber that doesn't even have a 1/2 thousandth tolerance. Perhaps your case gauge is dirty?

[Abenaki]

Are these bullets with a copper jacket? Copper plated? or lead ?

If they are lead boolits..........That would be about the normal size.
What were the size of your last batch of bullets from them?

Did you adjust your dies at all? Were the bullets seated straight?
Do you need to bell the brass more? Less?


Take care
Abenaki

[Abenaki]

[QUOTE Is there a possible future problem in running a lot of slightly oversized bullets? Any other danger from oversized bullets to watch out for?[/QUOTE]


.0005 over size is not going to mater with lead. It should not matter with copper jacket. So, did you use a caliper or micrometer to measure them?
Most calipers can not accurately measure .0005.


If they function ok, I would use them.
If you have any doubts......drop you load a hair.

Take care
Abenaki

[RugerNo1]

My .40 caliber Bear Creeks have always measured about .0005" oversized. Each o e has finctio end fine in my 2011.

[kurac]

its probably just the moly coating, but yeah 0.0005" oversized should not be an issue especially with lead.

[rsrocket1]

His problem is not just with the size, its as thenodnarb said, his gun can't seem to tolerate 1/2 mil oversized bullets. Unless his flair/deflair procedure needs more deflair. If the cartridge is hanging up somewhere else like the middle of the case, that's a different problem. The LEE FCD will iron out any oversized issues, but then he might end up with swaged down bullets which might cause leading.

[ParaLarry]

UPDATE

Thanks for all the replies.
I've been reloading these same Bear Creek .40 180 gr RoundNoseFlatPoint moly-coated lead bullets for almost ten years, have never seen this problem before.
Yes I do clean the case gauge at each reloading session.
Again, I measured the previous (old) batch of bullets and they were all spot on at .401
I measured first with a caliper then with a micrometer, most of the new bullets were .4015; ALL were over .401
I use a 550B with EGW undersize sizing die, Dillon seater, Dillon crimp set light at .424 (average) which resists thumb pressure against the bench.
Again, I fired the oversized bullets and they chambered and fired just fine BUT felt hotter.

UPDATE

Just heard back from my gunsmith:

Larry
Yes, I have seen and heard about incorrectly sized bullets from Bear Creek
They will generate excessive pressure, and possible failures to chamber. They need to be re sized.

So looks like I will get the Lee .401 sizing die and run them through my single stage press JUST to be on the safe side. And I will chrono a large batch of the new stuff after resizing them. I just didn't want to have to mess with the extra step.
Any suggestions where to get the Lee .401 sizing die in SOCAL without the lube (as advertised on Midway)? I already placed my 'Black Friday' order with them.

[thenodnarb]

Do you know that it is standard practice to size lead bullets .001 over groove diameter? My .45 I shoot as cast at .452 My .308 I shoot .309 lead powder coated bullets. Same with my .357, the bullets are .358.
Will it increase pressure? Yes, and that is sometimes helpful. But run a bullet through a .401 sizer die that is only .0005 bigger and it will feel like you didn't do anything to the bullet. The pressure increase in the barrel is likewise minimal. If you were already at or over max pressure then it is a serious concern. Personally I stay far away from max pressure. Since they chamber fine, that is good, but you shouldn't really be able to perceive a difference in felt recoil UNLESS your chamber is so tight that the case mouth is not expanding and releasing the bullet. They will still shoot but the pressure might be increasing significantly more.
What happens when you get some new brass that is .0005 thicker? That may cause the same chambering problem and high pressure problem as your "fat" bullets.
I think something else is going on entirely. It seems impossible to me that for 10k rounds you have received perfectly sized bullets, and that there have not been any wall thickness variations in your brass either(IF indeed your chamber is as tight as we are speculating). A chamber cast would be a good thing to do so you can measure your throat. At the very least, measure a fired case and see what the diameter is at the neck. If it is the same dimension as an unfired case, you have a crazy tight chamber, which could be dangerous. But again, I highly doubt that is possible considering your reloading experience and your history with this gun particularly. Something else has to be going on.

I just realized that you mentioned you are loading "long loads." I take this to mean that the bullet is seated over max length. So what is (probably) happening is that the slightly fatter bullets, which are now wider than the groove diameter, is being pressed into the groove at the end of the throat upon chambering. Normally you would never notice this with .001 oversized bullets because they are pressed into the groove upon firing, but because they are long, this is happening upon chambering. Your chamber isn't tight. If you seated your bullets deeper it would likely go away. And of course if you size them, you won't have a problem either. Personally I would just back off the powder charge a smidge and shoot them as is(if indeed they feel hotter).

[JagerDog]

I'm surprised you got damaged boxes, etc. I was at Bear Creek a couple weeks ago and he had a pallet full of these in 1000 pc boxes.