FINALLY - 5 Underwood 10mm Ammo Disections

[Intercooler]

Shadow,

             Gotcha and corrected it.

[RMM]

I'm supprised no one pulled down a 165 gr loading to see the difference from the 155 grain.

Does anyone have an Underwood 10mm 165gr load(s) they would disect for us and post the findings?

Are you guys still looking for the 165 gr. loads?  I've got both the Underwood 165 GDHP and TMJ.  I would be willing to sacrifice a few for the cause if needed. 

[REDLINE]

I'm supprised no one pulled down a 165 gr loading to see the difference from the 155 grain.

Does anyone have an Underwood 10mm 165gr load(s) they would disect for us and post the findings?

Are you guys still looking for the 165 gr. loads?  I've got both the Underwood 165 GDHP and TMJ.  I would be willing to sacrifice a few for the cause if needed.

I think we're okay with the 165s.  The_Shadow disected a Underwood 165gr Hornady XTP here -  http://10mm-firearms.com/factory-10mm-ammo/underwood's-lineup-135155165180220/

Since we've disected so many of the others along with the 165 XTP I feel we have a pretty good picture of what Underwood is doing overall, to the exent there's a good chance there wouldn't be much relevance going further.

Thanks for offer though!

[4949shooter]

Intercooler did say that sample was from an older box of Underwood. I am wondering about QC as of late.

[REDLINE]

Good Point

[RMM]

My batches are from the end of January.  They have the "Underwood" head stamp brass.

Maybe this weekend I'll pull a few down to satisfy my curiosity. 

Richard

[REDLINE]

If it works out I'ld be interested in your findings.

[sqlbullet]

Someone with a pipeline to Underwood (looking at you IC ) should put the bug in his ear to extend his website to include QC stats.

Stuff like % of loaded rounds verified by QC, and then variation reports on the QC findings....standard deviation and extreme spread on powder weights and cartridge overall length.  If they perform tests on things like neck/crimp tension, that would be great to report too.

Seems like it should be a relatively simple add, and a huge differentiator.

[Intercooler]

   I don't know anyone else that does it. Would that add to the cost of the ammo to have these QC steps done? I have no idea what's involved to do them.

[The_Shadow]

If the dies don't change position, most stuff will be very close to tolerance, however brass being longer or shorter would affect crimp issues.  Bullets that are either larger or smaller than proper diameter will have some affect on velocities and pressures. 

The most important issue is powder measurement for consistency and uniformity, this along with all the other factors being in tolerance will deliver the most shot to shot repeatability.

Care needs to be taken to check that nothing is out of spec, such as loose dies and die parts, press parts too.

[sqlbullet]

I would assume in their existing quality control, they remove X% of loaded rounds from the run, and measure head, case mouth, cartridge overall lenght, then pull the rounds and measure the powder charge.  I would further assume that if in a given lot they have above a certain deviation from the expected values, the lot goes under additional scrutiny. 

At least, I hope they do this, and I know that ATK does this at places like Lake City. My father-in-law is a retired Hercules/ATK employee.  His entire career was spent as a safety specialist in rocket motor, propellant and explosive handling.  He has visited Lake City a number of times to review their quality control and safety processes.

While I doubt a small shop can duplicate what ATK does, they can/should certainly mimic the basics of inspections of samples for each lot.  Assuming they already perform these checks and record the results, I am only adding publishing the results.  Cost to do that should be minimal.

[REDLINE]

I would assume in their existing quality control, they remove X% of loaded rounds from the run, and measure head, case mouth, cartridge overall lenght, then pull the rounds and measure the powder charge.  I would further assume that if in a given lot they have above a certain deviation from the expected values, the lot goes under additional scrutiny.

While I doubt a small shop can duplicate what ATK does, they can/should certainly mimic the basics of inspections of samples for each lot.  Assuming they already perform these checks and record the results, I am only adding publishing the results.  Cost to do that should be minimal.

Seems reasonable.

[RMM]

I will get some pictures up later, but I pulled down (3) Underwood 10mm 165 GDHP cartridges.

All three measured 10.2 gr. powder on my calibrated digital scale.  I don't have any 800x to compare it with, but it does look the same as the 800x I've seen in the pictures on this site.  The flakes are much bigger than Longshot (which I do have).

[The_Shadow]

RMM, did you see small tan flakes mixed in amogst the larger black flakes?  The tan flakes are the identifier in IMR800X, but it is hard to mistake the huge round disk flakes...  

[REDLINE]

I will get some pictures up later, but I pulled down (3) Underwood 10mm 165 GDHP cartridges.

All three measured 10.2 gr. powder on my calibrated digital scale.  I don't have any 800x to compare it with, but it does look the same as the 800x I've seen in the pictures on this site.  The flakes are much bigger than Longshot (which I do have).

Seems logical being that the 155gr loads I disected ranged from 10.5-10.7 grains, and the 180gr loads I disected ranged from 9.4-9.7 grains.  And of course they were also 800-X.