PPU factory loads too long?

[laxpatrick]

Picked up a box of PPU 120gr HPBT and some Hornady 123gr SST's.

New build, Midway Stoner barrel, 18", various other parts for the build.

Chambered the SST's - no problem.
Tried the PPU's - they won't fully chamber.

I've done a fair bit of reloading for 223, 243, 270 and 30-30.

Then I measured -
Hornady - 2.240 OAL - 2.710 with Hornady LNL Comparator and 4-25 Insert (best fit)

PPU - 2.240 OAL - 2.813 comparator

Anyone else have this issue?

Went to do some handloads - ended up with 120gr Sierra Pro Hunter Spitzer OAL of 2.170 and comparator at 2.765 - loaded conservative at 25gr or 8208XBR and large primers for the PPU new cases I got.

They seem to chamber fine, no land marks on the bullet.

I'd appreciate any input on those load numbers (primarily OAL/Ogee length).

Thanks!

LAX

[laxpatrick]

...or the Midway barrel chamber is too short. Looking around it appears that I'm not alone with this issue.

Guess I could seat the factory rounds deeper... May see what Midway has to say.

[LRRPF52]

Your chamber is too short. When I got the PPU 120gr MPT loads, I tested them in at least 5 different barrels and posted the results. I seated them fully into the chambers, then held them muzzle up so gravity should pull them out. All of them passed that test.

Satern, with a throat on the shorter end passed- I just double-checked it.

3 Different Lilja's passed.

AA passed.

Underground Tactical passed.

[lawndartmike]

I shot 100 PPU through my 16" AR Stoner barrel with no issues other than the powder being very dirty and they added an MOA to my groupings. I've never seen it documented who has made barrels for Midway or how to tell who made which ones.

[laxpatrick]

False alarm. Took the bolt out, did some more extensive lubrication and double checked pretty much everything.

It chambers the longer rounds just fine now, with no evidence of excessive length and the extractor works fine.

Sorry for crying wolf, or PPU in this case...

[LRRPF52]

When you say lubrication, I hope that doesn't mean the chamber or ammunition.

[laxpatrick]

When you say lubrication, I hope that doesn't mean the chamber or ammunition.

HAHA! No. Wow, I could just see pouring some breakfree on the bullets.

No, it was a spankin new upper, etc so it needed some more lube in all the right places. Thanks for checking though - you never know what folks might do.

[LRRPF52]

For those that are wondering why not to lubricate your chamber or ammunition...

The chamber needs a certain amount of surface adhesion in it to keep the case in place under pressure, otherwise bolt thrust increases substantially.

Additionally, oils are highly flammable at the temps and pressures in rifle chambers, and chamber pressure can increase to extremely unsafe levels.

On top of that, if most lubricants are applied to ammunition, they will creep into the primer pocket, and can neutralize the high explosive compound in your primer, creating a dud.