doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com #7.5 vs #8 Shot Performance in the Field

Beans,

Well that didn't take long. Only a 6 day break? I will entreat you to please take a breath on this forum. Lots of guys know a heck of a lot of stuff.

On to the subject matter...

The tests referred to above were conducted years ago, published in the DoubleGun Journal by Sherman Bell and Tom Armbrust, the series entitled "Finding Out For Myself."

They were extensive, and included all types and grades of both Damascus and fluid steel, including Krupp as I recall. You would will find it enlightening to read that series in it's entirety before making statements replete with absolutes.

Krupp was excellent, but Bell's tests showed the best of ALL types of barrels pretty much failed at the same pressure ranges.

I own Lefevers with Krupp barrels, and with Damascus. So long as I inspect the Damascus for fissures, I trust them about equally. The latter are certainly prettier.

Highest grade Lefevers offered Kilby or Whitworth fluid steel, Krupp went no higher than grade B...perhaps some A's.

As I recall there is also Birmingham proof house data which places both of those steel types surviving loads higher than Krupp and others.

I feel like Drew Hause may have something to share on that.

- NDG

Bell reported tests of two guns, both were Parker G grades, one Damascus & one Steel. Both guns were burst at pressures of around 30K PSI. The Boltiong had nothing to do with the failure of either, the chambers were burst in the wall between the chamber & the hole for the extractor leg.

Buck Hamlin tested a Lefever & an L C Smith, both Damascus, by re-chambering them to 3�" & started with the heaviest load using Blue Dot powder in the loading manuals. He went up from there. He stopped short of destruction o the Smith when he couldn't keep the gun Closed because that "BROWN ROTARY BOLT" kept un-bolting itself. The Lefever bolt performed admirably & he did continue loading it up to destruction. He did not actually measure the pressure as I recall, just used extremely heavy charges, well beyond proof charges. Neither the bolting nor the Breeching failed on the Lefever, also burst the chamber walls when the pressure went beyond the limits of the metal used.

So much for the great superiority of the rotary bolt. Its a good system, but it is not Head & Shoulders above any other good system.

2 piper,
Setting up an abnormal pressure test, run by an individual for either of these great american double guns proves nothing, except that the original engineering was fantastic for actual usage. The Hodge Breech work and either of these engineering designs proves that virtually no amount of normal pressure used for actual manufacturing of fire arms, will damage or distort the locking system in use with normal shells, although the LeFever engineering will need to be adjusted over time, and the Brown Rotary bolt will self adjust with wear.

Further non of these non scientific uncertified individual tests mean anything, they were not done in a scientific certified manner or method, nobody knows if the testing was even done correctly, by these individual testers, no matter what publication they appeared in.

Nudge,
Knock off the superiority crap, it does not work with me. Intreat me to none of your insults or I will now return them in spades.

RGD/Dave
L.C. Smith Man

Beans,

As stated, the testing was done by Tom Armbrust of Ballistic Research in Illinois. All I can do is try to lead you to the data for you to read for yourself.

Not only was the testing NOT "nonscientific" or "uncertified," as you blindly guessed, it was done by a man who does this and other types of load and pressure testing...AS A BUSINESS.

There is no superiority here...we are all students. Which is why you just cannot speak so resolutely about matters on which you're only supposing...without embarassing yourself.

Lots of guys do real research here, either 1st or 2nd hand. Opinions can be quite valid, but in the presence of hard data one is wise to at least reconsider his 'best guesses.'

These tests were about as good as anyone has yet published. And they tested many, many barrels. Bell had put out the call for donor barrels, and lots of people responded.

I spoke extensively to Tom about their conclusions. This wasn't two toothless dudes on YouTube trying to blow stuff up in their grandmothers back yard.

- Nudge

Dave;
I explained the bolting/breeching system in an earlier post. Apparently you still have no comprehension of it. "Both" the Lefever & Smith are self adjusting in the bolting. The top lever will move left on either as the bolts wear.

The Lefever "CAN" be adjusted for hinge joint wear, the Smith "Cannot". You can call that better engineering for the Smith IF you choose to, I Don't.

I will add that I have two guns with absolutely no wear compensation to either the hinge or bolting. One is a J P Clabrough , the other a J P Sauer & Son. Both are SLNE guns, both are more than 100 years old & both are still tight. It just may well be the case that the friction in a self adjusting wear compensation device creates as much (Or More) wear as it compensates for.