357Sig KB w/KKM BBL Underwood Ammo

[Intercooler]

    I would have to see what the reloaders like Shadow think about the powder charges. I know 800X is big flake and might be 1-2 flakes make an impact.
    When talking COL that's another thing I don't know about. What's acceptable and where would you see a red flag on it?


   

[4949shooter]

I think Redline may have hit the nail on the head. We spoke about pushing the load limits a few months ago right here on this forum.

I am sorry to say, I think it was only a matter of time before this happened.

I certainly hope Kevin reevaluates. He seems to be a good sort.

[4949shooter]

These are what I have and they fit like batting gloves but better. They breathe and feel like a second skin! No complaints here with quality, fit or function in my two times out with them and they aren't broken in yet.

http://www.amazon.com/Hatch-SGK100FR-Street-Kevlar-XX-Large/dp/B003X3NCTW/ref=sr_1_6?s=sporting-goods&ie=UTF8&qid=1362329205&sr=1-6&keywords=hatch+kevlar+gloves

Thanks ICooler. These aren't the ones with the X11 liner, are they?

[Intercooler]

Here's the thread when I got them:

http://10mm-firearms.com/general-discussion/christmas-gun-gifts-post-them-up!/msg8886/#msg8886

I plan on calling Kevin this week and see what are his thoughts and/or what's new.


If PBR is using #9 it's hard to go to an extreme overload by capacity. I will ask Anthony and see if he will share. That would be the safe pick right? Let's see what this batch of DoubleTap I'm sending is using for powder.

[4949shooter]

Okay thanks. You got the fire resistant model I see.

Will be interested to hear what Kevin has to say.

[REDLINE]

If COL is shorter than a recipe calls for, then pressure during firing rises compared to what was originally intended at a set COL.

Too short of a COL can happen from two different issues that I'm aware;

1)  Sloppy load practice where tolerances simply aren't being kept.

2)  From any number of ways a bullet once loaded to a correct COL, later, gets pushed farther into the case before firing.


For example with the UW 10mm 135gr Nosler bullet load that we've seen range from 1.249" - 1.252";  Let's say Kevin intended for them to be loaded at 1.250" exactly for the pressure he intended to achieve.  Then, any cartridges that end up at .001" shorter, like the 1.249" ones, probably won't be a big deal, even though pressure may have risen a tiny bit. 

But if his intentions were a COL no shorter than 1.252", then -.004" (for any rounds coming in at a COL of 1.249") could start creating an issue in too much pressure for rounds already loaded hot.  Then add an extra few tenths of a grain of powder over what was intended along with the -.004" COL, and ugly things can begin to happen real quickly.  Best Case Scenario = bad smilies and primers that just fall out.  Worst Case Scenario = banana peeled barrels and cracked frames.  So far we seen everything from zero issues to both best and worst case scenarios I mentioned.

I just weighed a single sample of 800-X on my Redding Number 2 Beam Scale.  That single sample showed it took 10 flakes of 800-X to equal one tenth of a grain (none of the gold colored specs were in the sample).  If that's correct on any kind of average, then the range of .5 grains off with the UW 10mm 135gr load equals around 50 flakes of 800-X powder.

What would be nice to know is the actual intended recipe Kevin is using for the 10mm 135gr load.  Then we could actually know how far off his loads are or aren't, and how much.  Problem is they are sloppily loaded to the extent it's hard to guess.


PS - just checked another sample of how many flakes of 800-X are in .1 grain.  This time it took 11 flakes.  10 flakes wouldn't quite do it this time.

[The_Shadow]

With the Bottle-Neck cartridge the bullet selection can be a determining factor...Olgive may not allow for a good purchase during tape crimps.  Like NATO style 9mm bullets.  I like 0.356" bullets in mine, I am also about to test some at 0.357" This will raise pressure some too.  Bullet which are smaller in dia. can also lead to loose fit.

Also the sizing of the neck area and using an expander which is not too large of dia. to straighten up the neck, inspection here to see if it is the cause loose fit.

If the cartridge is fed at an odd angle and the bullet comes in contact with anything during the feeding it maybe pushed back to cause a setback issue.  Then if a cartridge is dropped it can push the bullet back also.

Many people were loading with powders such as AA#9 to be compressed and not allow the bullet to be pushed back any.

[REDLINE]

Many people were loading with powders such as AA#9 to be compressed and not allow the bullet to be pushed back any.

That's a great idea.  I may give that a try with reloaded brass in conjunction with 135gr bullets in 10mm.

[P33v3]

So for us unwashed, non-reloading, heathens are you guys saying Underwood is not safe out of my Smith & Wesson 1076?

[evanica]

kudo's to underwood

[Yondering]

If COL is shorter than a recipe calls for, then pressure during firing rises compared to what was originally intended at a set COL.

Too short of a COL can happen from two different issues that I'm aware;

1)  Sloppy load practice where tolerances simply aren't being kept.

2)  From any number of ways a bullet once loaded to a correct COL, later, gets pushed farther into the case before firing.


For example with the UW 10mm 135gr Nosler bullet load that we've seen range from 1.249" - 1.252";  Let's say Kevin intended for them to be loaded at 1.250" exactly for the pressure he intended to achieve.  Then, any cartridges that end up at .001" shorter, like the 1.249" ones, probably won't be a big deal, even though pressure may have risen a tiny bit. 

But if his intentions were a COL no shorter than 1.252", then -.004" (for any rounds coming in at a COL of 1.249") could start creating an issue in too much pressure for rounds already loaded hot.  Then add an extra few tenths of a grain of powder over what was intended along with the -.004" COL, and ugly things can begin to happen real quickly.  Best Case Scenario = bad smilies and primers that just fall out.  Worst Case Scenario = banana peeled barrels and cracked frames.  So far we seen everything from zero issues to both best and worst case scenarios I mentioned.

I just weighed a single sample of 800-X on my Redding Number 2 Beam Scale.  That single sample showed it took 10 flakes of 800-X to equal one tenth of a grain (none of the gold colored specs were in the sample).  If that's correct on any kind of average, then the range of .5 grains off with the UW 10mm 135gr load equals around 50 flakes of 800-X powder.

What would be nice to know is the actual intended recipe Kevin is using for the 10mm 135gr load.  Then we could actually know how far off his loads are or aren't, and how much.  Problem is they are sloppily loaded to the extent it's hard to guess.


PS - just checked another sample of how many flakes of 800-X are in .1 grain.  This time it took 11 flakes.  10 flakes wouldn't quite do it this time.

Redline, I think you might be making too big a deal out of some small variances. +/- .002"-.003" for OAL, and +/- .1gr powder, is completely normal for good loads. You're right that that 135gr Underwood load is a bit sloppy, but the rest you list are within a normal acceptable range. Velocity and pressure variations between those rounds with the exact same OAL and powder charge are often greater than that caused by the variations you list above.

My take is that Underwood is simply loading some of these too hot for mass production and use by the general public. A load worked up in a specific gun, that is max for that gun, is one thing, but may be too hot for another gun. I don't think Underwood is loading to the lowest common denominator, so to speak.

[sqlbullet]

I don't have any experience with 800X.  But with Blue Dot and Longshot loads I have worked on, I don't see statistically meaningful changes in velocity, and by extension pressure, from a few tenths of a grain more or less powder.  Same with seating depth.

Like Yondering says, it takes more than .3 grains and .003" to make a difference, even at the edge.

But, if the bullet style didn't crimp well, it is possible the bullet got set back .030" or more on the way into the chamber.  And that could make a difference.  It is also possible with a large flake powder like 800X that a partial discharge occured in one case and the rest of the powder plus a full charge made it into the next.

Either of those scenarios could have a bad effect.

[REDLINE]

Redline, I think you might be making too big a deal out of some small variances.

My intention isn't to make a big deal out of small variances.  I've only pointed out known fact.  The known fact goes beyond small variances in a few disected UW loads.  The known fact also includes: velocities that shouldn't be achieved, at least one primer that just fell out, horrendous smilies that could have easily ended in disaster, and at least in 357SIG a split barrel.

Velocity and pressure variations between those rounds with the exact same OAL and powder charge are often greater than that caused by the variations you list above.

That makes no sense.  You say more variation is often greater when caused by less variation.  That certainly isn't true unless you're right at a powder level where that powder, if suseptable, poops out anyway.  In this particular case we're mostly talking about 800-X which is a powder that seems happy to keep on giving and doesn't know the meaning of the word quit.  Either way I'm not sure why you'ld even say that.  Like I said, I've only pointed out facts.  Those facts are what they are.  Attempting to demean them doesn't change them.

I agree that most of the variation we've come across in the actual disecting of rounds so far is relatively minimal in itself.  But when limits are already being pushed it doesn't always take much.  And that brings us to the last of your post I quoted you on... 

My take is that Underwood is simply loading some of these too hot for mass production and use by the general public.

Probably more true than most of us would like to believe.  It's also reason to support how load variances that are normally no big deal can begin to become bigger deals real quick.  For me it gives reason to at least pay very close attention.  Again, it's not my intention to make a big deal out of the facts.  For me it's simply about being aware and paying closer attention than one might otherwise.  I don't know what the furture will bring, but it will present itself soon enough.  Hopefully it doesn't bring anything to light worth blinking at.

[REDLINE]

...it takes more than .3 grains and .003" to make a difference, even at the edge.

I disagree that .3 grains more of 800-X doesn't make a difference at the edge.  We don't have to argue it, I'm just saying my opinion from having worked with the powder myself.

The .003" I agree as I already more/less stated.

[Intercooler]

   I phoned up Kevin today and it's always a joy to talk with him. They never had a 10mm issue so no changes planned at all there. He did say they may make a change to put everything shoot-able in the Delta.  Kevin said this is the first time any kind of Kaboom has happened with his ammo. Could have been set-back and he said even a hard drop by the UPS guy could do it. I asked about being on the edge and didn't get the sense he felt that way.