A few thoughts on 'Over bored ' barrels

I have had far too much time on my hands and been thinking about overbored barrels as in Beretta DT11 and some of the American overbored monsters.

If this overboring is so brilliant and revolutionary ? Why hasn't it caught on?

Why does Neil Winston's research as posted earlier on this website not show any significant advantage , and why if it is so good can a 28 bore or 20 bore in skilled hands perform equally as well as a 12 bore and finally , what about correct obturation when using fibre wadded cartridges?

Lots of questions , I will be interested in the replies.

It would seem that an idle mind is the tool of the Devil.  My personal opinion is is banging on who GAF anymore.  If you really really really want some discussion I suggest that you give a search at trapshooters.com where you will find a multitude of voluminous and opinionated threads/comments! 

bon appetit

I might add that NOWHERE will you find any actual data or substantiated evidence of any kind contrary to what Mr. Winston has published.  Go figure, eh?

DUNNO  !

Re overboring... 12bore UK standard dimension is anything between .729 and .740 inches. If a barrel is stamped 18.4 it measures from .724 to .728 which is not quite 12 bore but in uk proof is actually  called 13/1(.ie between 13 bore and 12 bore.) So called back bored barrels i seem to recall may be stamped 18.6 (.732) or 18.7 (.736) or maybe 18.8 (.740). As you can now see all are STANDARD 12 bore dimensions and have been for a couple of hundred years. Anything larger than .740 is heading towards 11/1 bore and probably will not be efficient with 12 bore loads. SO nothing new in so called " back boring" and I do believe that comprehensive tests (which can be found on the Internet) have showed that the variations in cartridge performance within 1 carton of cartridges is far greater than any performance change brought about by so called back boring... Hope this helps..

Its back and its boring!  :biggrin:

I view of my testing results

http://www.claytargettesting.com/Bore_Diameter/Bore_Diameter.pdf

...and the total lack of any testing at all by either the manufacturers or the so-call "gun testers" in the shotgun magazines (including the UK one I subscribe to for its strange but interesting shell-testing articles), I think no one should expect anything special performance-wise from the improved models of whatever they have been gulled into buying by their general lack of success with whatever they have been shooting until now.

I have read every "test" of DT11's I can get my hands on and have yet to see anything beyond a rewriting of the claims of Beretta about the miracles wrought by the Stellium bores they feature. The claims could be supported/demolished by an afternoon's work if the writers were interested at all in telling their readers what's going on. 

Jezek

Jezek/ Neil ,

 But of course the journalists would then risk the wrath of Beretta and probably lose advertising revenue .

We have a journalist that rolls out gun reviews in most magazines and is yet to have a bad one , amazing .

If that were the case we would all only need one gun and life would be simple .

Salopian said:

Jezek/ Neil ,

 But of course the journalists would then risk the wrath of Beretta and probably lose advertising revenue .

We have a journalist that rolls out gun reviews in most magazines and is yet to have a bad one , amazing .

If that were the case we would all only need one gun and life would be simple .

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Only one? 

I was alluding to Vic Harker, I know we also have many more.

If a DT11 is so wonderful where does that place a 20 bore or 28 bore shooting 1oz of shot ?

I have just moved from a Browning 725 with 18.7 barrels to a lovely DT11L with 18.8-18.6. So far my conclusions have been that the barrels are an absolute pig to clean, the patterns are tighter than expected and it benefits from an open choke (IC) but the recoil impulse is reduced making it very comfortable to shoot (weight is pretty much the same as my 725 as well). Not shot any fibres yet in a decent environment or patterned them, so it's a wait and see. So far from my point of view the claims are not complete mumbo jumbo, whether the changes are necessary is another matter.

Jonny English said:

I have just moved from a Browning 725 with 18.7 barrels to a lovely DT11L with 18.8-18.6. So far my conclusions have been that the barrels are an absolute pig to clean, the patterns are tighter than expected and it benefits from an open choke (IC) but the recoil impulse is reduced making it very comfortable to shoot (weight is pretty much the same as my 725 as well). Not shot any fibres yet in a decent environment or patterned them, so it's a wait and see. So far from my point of view the claims are not complete mumbo jumbo, whether the changes are necessary is another matter.

Click to expand...

18.8. Interesting.. I was led to believe that the early ones were well over19 and that was a problem with some cartridges.   No experince myself of patterns or how true that is. Ihave to say the DT11 is possibly the softest gun I've shot. Whether that's dpwn to bore size or weight  I have no Idea.  

Use fibre in a Browning 725 barrels @ 18.8mm for years now never had any proplems, hard to see much difference between plastic and fibre, as far as l can see kills excellent (when I'm on em!)