Email from Kevin at Underwood

[RRMan03]

I ask Kevin about his hottest loads and the support required by the barrel for the G20 and G29. He said if they were recommending it would be Bar Sto Barrels but the simple fact was that the factory Glock barrel had more than enough support around the case on their ammo. That the only thing the other barrel did was help accuracy due to tighter tolerances. Now I do not claim to know anything on this subject except on the accuracy part and that is because I can shoot having been taught in many different courses over the years and knowing how to handle both a handgun and a rifle.As a gunsmith I suck. As a shooter you do not want me shooting at you. Not bragging just telling it like it is. If the gun works I can work it. If the gun does not work I am as dead as yesterdays news.That being said what are the reasons for Ka Booms. We all know case failure,over pressure,poor construction of the bullet. Now give me the other things that can cause it.Lets leave a sorry gun out of it. Ammo only.I hear more bad things from large factory ammo makers like FTF's etc usually not Ka Booms ,cause they are so weak, than I do from the smaller manafactures.When factory ammo explodes someone somewhere did not do their job period.Maybe the powder maker,maybe the brass maker, maybe the constructor but somewhere some how some human had a hand in the Ka Boom. Just my thoughts. I am leaving reloaders alone here and any manafacture that exceeds pressure limits is asking for it.

[REDLINE]

That being said what are the reasons for Ka Booms. We all know case failure,over pressure,poor construction of the bullet. Now give me the other things that can cause it.

The only other thing I can think of is someone modifying their gun in a way that ends up compromising its integrity regarding handling pressures it was originally meant to.

As far as case failures go, this can happen 3 different ways that I'm aware, that don't all equal a KB. 
1)  The brass case partially splits lengthwise (sometimes around its circumference), but all bullet, powder, and pressure still go out the end of the barrel we'ld prefer. 
2)  The brass case blows at the 6 o'clock chamber position via lack of barrel chamber support (may or may not be because of an overloaded powder charge, but usually seems to be in my estimation).
3)  The brass case splits lengthwise in multiple areas (shreds would be my terminology) usually resulting in a more catastrophic KB where the barrel chamber itself splits (sometimes in the form of a crack, while other times gaping).

Not sure there are other ways or reasons except for something unheard of like the gun being at -300 degrees F when it was fired.

When you say;  "...poor construction of the bullet.", do you mean sloppy load technique like as in adding too much powder or a bullet not crimped in the brass case properly?

[REDLINE]

...but the simple fact was that the factory Glock barrel had more than enough support around the case on their ammo.

I think that would be 99.999% true if none of his 10mm loads left the factory loaded beyond the 37,000 PSI he claims their intentions to be.  CLEARLY that hasn't always been the case, with some of his 10mm rounds leaving the factory surpassing that level.

[RRMan03]

Yes I meant sloppy loading.

[Intercooler]

I don't own a firearm that ever needed a barrel swap to be accurate or shoot the round it'schambered in. All that seems crazy to me

[sqlbullet]

Need has variable definitions.

I will say this about Underwood.

Colt says the Delta Elite will handle any 10mm Auto ammo that is loaded to SAAMI spec.  Colt's ran fine with Norma ammo.  There were not huge reports of KB's. Numerous gun writers have also said the Delta Elite works fine with SAAMI spec 10mm ammo.

Yes, the Delta Elite barrel clearly lack case head support other designs offer.  Regardless, Colt still stands behind their product as capable of SAAMI spec ammo.

Kevin is blunt that his ammo is hotter than he thinks the Delta Elite can handle.

This leaves us with one of two options:  Either the whole of Colt and the gun magazine industry is wrong and the Delta Elite won't handle true SAAMI spec 10mm Auto ammo, or Kevin's ammo is not to spec.

That may or may not be in the direct control of Underwood.  The_Shadow has commented that Starline brass may not be up to snuff.  If that is the case, then the ammo may well fall withing the SAAMI pressure guidelines, but still be out of spec.

I don't have the means to validate which is which.  I also don't have any 10mm that don't have ramped barrels.  And I handload and don't buy commercial ammo.

But is is an interesting point to consider.

[Intercooler]

Colt and Glock are the two companies are making barrels for. Says something

[RRMan03]

Both valid points. If they need aftermarket barrels then the ammo is out of spec. Wheather it is Kevins fault or not is not the point. He is the end seller.He stands behind what he sells.

[sqlbullet]

Here is some food for thought that I didn't cover related to levels of "need".

I grew up in rural Indiana in the 80's.  Starting at age 16 we all gained a new hobby.  We worked on cars.  Cars, that in point of fact, operated just fine.  My car got new struts, new axle half-shafts, a new fuel pump, new spark plugs, new tires, a new shift knob and a new stereo, complete with new 6X9" co-ax speakers in the rear deck.  Teenage boys work on cars, whether they are broken or not. Granted, all those parts were a little worn on my car, and the new stereo sounded better, but all the parts I replace except the tires were perfectly serviceable for another 20-50K miles at least.

Gun guys tend to be the same.  We accessorize our guns.  Rail lights, night sights, crimson trace grips or fancy wood ones.  And barrels.  Nothing yells "upgrade me" like a barrel.  I mean it is THE gun.  Everything else is the mount or the ignition system.  But the barrel...that is where it all happens.

And they are relatively inexpensive and on a Glock especially they are easy to upgrade.  All the is left is the need for an excuse.  And Glock provides us a good one, right in the manual.   "4. No liability whatever can be accepted if inexpertly manufactured or inexpertly filled ammunition is used." is the current language.

Pretty soon this is attributed to the polygonal rifling of the barrel and a "need" is born.

If you are going to run hot-rod ammo, a barrel built to tighter tolerance and with more support is surely an excellent idea in a Delta Elite.  It is a pretty good idea in a Glock.

But it is not needed if you are going to buy or load ammo that is not on the "hot rod" side of the fence.  You could run Winchester Silvertips or Buffalo Bore 180 JHP's for a long, long time in a Delta Elite with nary a kaboom, and likely not many smiles.

[Intercooler]

True but some of us purchase the ones who can go mild or wild as-is 

[RRMan03]

And back to all my questions. I like to shoot full power most od the time. Not overloads that i know of but full powr 10mm. In a Glock do I need to change from the factory barrel. Some say yes,some say no,Kevin says not with his ammo so I just do not have a clue. For accuracy drop in probably better for just shooting OEM.

[REDLINE]

And yet you've seen fit to modify numerous parts on your beloved mild-wild as-is EAA yourself...aftermarket sights, aftermarket firing pin block, cone guide rod, aftermarket extra long lightweight firing pin, aftermarket hammer spring, aftermarket shock buffer,...

So much for as-is.

[REDLINE]

And back to all my questions. I like to shoot full power most od the time. Not overloads that i know of but full powr 10mm. In a Glock do I need to change from the factory barrel. Some say yes,some say no,Kevin says not with his ammo so I just do not have a clue. For accuracy drop in probably better for just shooting OEM.

Look bro, you can take all the chances with Underwood Ammo you want.  Chances are you may never have an issue with your stock Glock barrel safely shooting Underwood ammo.  But clearly there have been issues with stock Glock stock barrels (among other barrels of other platforms like the Delta Elite barrel) shooting Underwood ammo because it's a fact some Underwood ammo has left the factory loaded beyond 37,500 PSI.  Take the chance or don't, it's up to you.

I for one will not run Underwood ammo in my stock Glock barrels at least until I've seen a positive change in the way Underwood is loading their rounds.  So far I haven't seen it.  Kevin has proven himself to be full of it from the standpoint we've seen negative issues (proof) with his ammo from two standpoints.  One, without question some of his ammo has left the factory loaded easily beyond 37,500 PSI, and Two, clearly this has caused issues with a good handful of factory barrels.

It may be different if we only ever saw an issue once.  Like a fluke or something.  Unfortunately there wasn't a single fluke occurance, but rather a few at least.  Again, if you want to take the chance, go ahead.  You may never have an issue.  But so far we know for a fact that if you are going to have an issue it will more than likely be with Underwood ammo.  What else do you need to know?  Take the chance or don't, it's up to you.  Clearly though you will be taking a chance that may or may not ever bite you.

The above all in reference to 10mm Auto. 

[RRMan03]

Thanks Redline for the input. I am not one to turn a blind ear to the fact that running at top sped wheather in a car or a gun can and will lead to bad things. I have considered a BarSto Barrel but after putting that in am I still at risk? If the ammo is out of spec I tend to say yes. There are many opinions on here about Underwood ammo and from what I have shot I like it but that is not saying if it is not QC and checked by lot that bad things can happen. But my question still is by changing the barrel if the ammo is still over pressure do you solve your problem? Opinions and thanks.

[Intercooler]

But no barrel 

The cone rod helps in the long run. Same for most the others but didn't do a hammer spring. Could have shot it totally as-is for years out of the box with the nastiest stuff.