OAL/BTO for 7mm PRC factory ammo?

[entoptics]

Looking to troubleshoot what I suspect is a VERY short throat, and would like to know the OAL and/or base to ogive for factory ammunition with a 175 ELDX and 180 ELDM for a 7PRC. Hoping there's some folks on here who have a box and a caliper handy to measure for me.

TIA

 

[MagnumManiac]

More importantly, what rifle are we talking about?
I have only ever come across this once and it was a complete F up by Remington. Six rifles came in with zero rifling and short chambered, all rifles were marked 7-08…how they ever got exported here is beyond me.

Cheers.

 

[bowhunter123456789]

Hornady Precision Hunter 175 ELD-X CBTO 2.595. COAL 3.290

 

[MOA or bust]

I wish the OP would elaborate on his problem a little more, perhaps we all can learn something.

 

[entoptics]

I was trying to be as parsimonius as possible, to avoid wasting peoples' time with irrelevant details (and potentially irrelevant replies with advice I don't yet need or want), but since you asked...

Based on the measurements provided by @bowhunter123456789, my 175 ELDX @ 0.02" off the lands is almost identical to the Precision hunter, though substantially shorter than I expected from a cartridge designed to keep the bullet out of the powder volume, as well as compared to another 7PRC barrel I had (returned as defective for other reasons, and replaced with this one).

What really has me concerned, is that the180 ELDM and 190 A-tip are ~0.20" and ~0.07" shorter to the lands than the 3.32" OAL quoted in the Hornady Manual. This is particularly weird, since my 7mm Mag, as well as the other 7PRC barrel had the ATIP and ELDM at very similar OAL/BTO to the ELDX.

Something seems wrong, but I like to get my ducks in a line before confronting a manufactuer. Since I only reload, and have no factory ammo to compare, I was hoping the fine folks here at LRH could help me determine if the throat is so short as to not even allow for factory ammo. In my book, that would put me squarely into a "warranty" issue, as apposed to "I wish it was longer" issue.

So...Anyone have some data on some 180 ELDM factory ammo, so I can check that off my list?

 

[MOA or bust]

Is this a pre-fit barrel with the chamber cut at the manufacturer?

 

[entoptics]

Is this a pre-fit barrel with the chamber cut at the manufacturer?

Yep.

 

[Kimber7man]

OK here you go, factory 180 ELDM ammo, 5 rounds measured

BTO:
2.464"
2.464
2.462
2.462
2.462

COAL:
3.294"
3.292
3.290
3.293
3.290

 

[Kimber7man]

Let us know what you find out!

 

[MOA or bust]

Just curious kimber7man, how do you measure the CBTO on a cartridge?

 

[std7mag]

Just curious kimber7man, how do you measure the CBTO on a cartridge?

Essentially you have something that fits over the nose of the bullet and touches the ogive.

Problem is, if you aren't using the same piece over the tip of the bullet that sits on the ogive as the other person, CBTO is a meaningless measurement.

For instance I can use a casing from a 25ACP to do a Cartridge Base To Ogive measurement.
It does sit on the ogive.
But it will only mean anything to me.

So if one person is using a Hornady tool, and someone else is using a Redding tool for instance, the readings can be completely different.

You may get a few thousandths difference in COAL, measuring the same bullet.