Boxed ELD pierced primer

[1911man]

So earlier this week I took my Alexander arms 16" barrel to the range for the second time and I noticed most of brass had high pressure signs as well as quite a bit of kick compared to my other rifles. On the last round I shot I had a pierced primer which made me decide to stop. I analyzed my brass when I got home and 80% of them had flat primers and 5 or 6 had craters. I did the good old drop the bullet in the barrel test and low and behold the round would not seat all the way in the chamber when dropped lightly. I couldnt even push it it in with my finger. I had to then use the bolt to force the round into the chamber and pull on it to eject it. The bullet has rifle marks on it. So I figured its the chamber not the ammo. But not so fast..

I then go out today with my 20" AR15parts.com barrel and the same set of 3 boxes of ELD ammo. This barrel has shot roughly 100-150 rounds of boxed ELD ammo without a hiccup and quite accurately I might add. I noticed harder recoil, flatter primers, and low and behold had a pierced primer this time out.

I still think my AA chamber was cut too short but is anyone else having pressure issues with this ammo? I know I read a post earlier this week where a guy had a pierced primer. Anyone else?

[mdram]

did bolts come with barrels?
wrongs face depth?

[1911man]

did bolts come with barrels?
wrongs face depth?

The 16" came with a bolt from AA and the 20" has a bolt from another brand.

[rabiddawg]

If I'm reading you correct, both functioned fine with prior ammo. You changed ammo and this issue surfaced with two different guns. Hmm. Sounds like there is something not right with the ammo.

[A5BLASTER]

Thanks for the post i will keep an eye on the brass from the ELD ammo i have.

[Commander184]

What's your bolt face depth and bolt total length? There is a similar thread goin on right now

[1911man]

What's your bolt face depth and bolt total length? There is a similar thread goin on right now

I havent had time to measure. It is important to note that I have fired 100-150 rounds of boxed ammo and some handloads through the 20" barrel without seeing any pressure signs. The 20" is a type 1 bolt and the 16" is a type 2, again straight from Alexander Arms.

[davidj]

What is the lot#. I have 5 boxes of it.

[1075 tech]

If both rifles previously shot well without issues with factory ammo and you now have an issue, I'd check the ammo. Measure OAL. Compare it other factory ammo. Call Hornady with the info and lot number. Let everyone else know what they say. Could be a bad lot.

ETA: Make sure the bolts didn't get switched. Same caliber but with different bolts.

[LRRPF52]

What are your bolt OAL measurements, and bolt face depths?

What's the lot of the ammo?

[1911man]

Lot # is 3163820, all of my boxes are the same lot number. I bought 200 rounds at once and this is the last of that batch. I definitely did not switch the bolts as one is in a side charging upper which I have to unscrew the charging handle to take the bolt out and I have not done that since assembling it.

I know for sure the 20" was firing the ammo without pressure signs in previous outings but I cant say that about the 16" because I have fired very few rounds from it and had to shut it down because of that pierced primer after a very low round count.

[1911man]

I havent had a chance to do any measuring but will when I get a free moment.

[Boostmeister]

Did you chrono the loads? Were they faster than previous loads?

[1911man]

No I did not Chrono the loads that had the pressure problems.

I will have time to measure my bolt this weekend. Anyone want to give me a tutorial on how to measure the necessary areas with a pair of digital calipers?

[Casper77]

No I did not Chrono the loads that had the pressure problems.

I will have time to measure my bolt this weekend. Anyone want to give me a tutorial on how to measure the necessary areas with a pair of digital calipers?

Im thinking use the depth blade for the bolt face. This was helpful for me... http://www.65grendel.com/forum/showt...light=Calipers

I don't know if this will be of any help since you are working with the ELD's but I've had several pierced primers from Hornady 123gr SST's this winter. Out of the 80 I shot probably 6-8 were pierced. I also had random "really flat" primers. I threw the boxes away already so no lot numbers. They shot okay, 1.25"-1.5" groups @ 100 I'd say on average. Either way I'm not shooting them anymore. I don't think it was my chamber. I've been loading Nosler 129 gr ABLR to 2.26 oal without any issues.