Barrel dimension and thicknesses

[Old Boggy]

I`m after a bit of  advice regarding the dimensions that I`ve been given prior to a potential purchase of an English 16 gauge side by side non ejector.

The gun is choked 1\4 and 3\4 which is fine. However, the dimensions that I`ve been given of the barrels are as follows -:

RH stamped  16.66, size is 16.1668

LH bore size stamped 17/1 = 665, size 667 so just 2 thou over.

RH wall thickness = 9 thou

LH wall thickness = 7 thou

I have copied the details exactly as they were sent to me so not sure if they are missing decimal points etc. but it is the wall thicknesses that surely must be wrong. I would have expected the wall thicknesses to be in excess of 20 thou, but could be wrong. Hopefully this is a typo by the gunshop so I have queried it and await a reply.

Perhaps `Gunman` or others out there who are far more knowledgeable than me, could offer their comments/advice.

Many thanks,

OB

Sorry, pressed `submit` too many times !!

[Dave at kelton]

I agree got to be a typo those dimensions are paper thin. Hope you get a good response from the gun shop.My concern would be they come back at 17 and 19 thous in which case I would walk. Obviously the reverse would be the case at 27 and 29.

Dave

[panoma1]

I would consider walking anyway! If they can't provide basic measurements correctly they should perhaps consider a different business?

[wymberley]

There is another possibility. Being English, the gun will be stamped in Imperial measurements, but what if, with a slip of the pen, the latest are metric? 9 = 0.9mm = c.0.035" and 7 = 0.7mm = c 0.028". Just a thought. Mind you, having said that I'm at a loss with the RH bore stamping - if that is metric then the diameter has somehow got smaller - c0.656" against c0.636".

[JohnfromUK]

The metric system is a curse.  I don't understand what you have been sent at all.  One barrel (RH) appears to have been quoted in (presumably) metric at 16.1668 against stamped 16.66 - so it is well under the nominal dimension (by 0.49 mm or 0.0194").  This seems too far to be correct as 20 thou is two proof gauge sizes.  Therefore I conclude 16.66 is the main bore and 16.1668 the might be the choke - 20thou choke is near 1/2 choke - which is tighter than you have been told.

16 Bore nominally should be 0.663" or 16.83mm  (17 is 0.650" or 16.50mm) from figures drawn from the internet.

The left barrel has been quoted in Imperial units.  If it was proofed as a 17/1, that I believe to be approx 0.657 (NOT the stated 0.665).  If it is now 667, by my reckoning on the limit of proof.

Conclusion - I don't understand what has been sent.  That may be me being thick.  If some dimensions are metric this indicates reproof, but both original and reproof would have been applied to both barrels and you may have some original figures (e.g. 17/1) and some reproof figures (the metric ones).  Quoting a mix suggests the vendor doesn't understand the implications, which is very worrying as it is his responsibility in law to ensure any gun sold is in proof.

On wall thickness - you really need a minimum of 20 thou (though it isn't a legal requirement).  Thinner can be usable, but is easily damaged/dented and allows no margin for future dent removal.  7 thou and 9 thou would be dangerously thin.

I think you have three options:

1. Visit with correct gauges and make your own assessment
2. Get a gunsmith who uses a logical system to measure it for you
3. Walk away.  With measurements you don't understand and wall thicknesses either unknown or dangerously thin, its not something to buy without full clarification.

Basically you need to be sure that (a) the gun is in proof, and by a decent margin (not just marginally inside) and (b) the walls are of sufficient thickness (usually taken as at least 20 thou) and finally (c) that the barrels are sound and undented/bulged.

Edited January 13, 2018 by JohnfromUK

[Old Boggy]

Many thanks for the replies.

As it appears that the seller (trade) does not quite understand or perhaps misinterprets the markings, I think that it would be wise to pass on this one.

Thanks again for all your replies and PMs,

OB

[Old Boggy]

I have just received some further pictures of the gun which shows that the top lever is well over to the left indicating that the gun has other 'wear' issues so definitely to be walked away from.

Thanks again for your very informative replies.

OB

[Gunman]

I would guess the seller is so ignorant of British proof marks  as the way he has described them do no make sense , the 16.66 is not a proof size in any marking ever employed by the proof house'es . If it is a shop I would ask for clarification and if he is and is offering a gun for sale with those wall thicknesses then he should not be in business .

17/1 =.655" which goes out @ .669" so if size of.667" is correct then it is in by .002" not over .

I will accept typo's but not ignorance or down right bad practice  form people within this trade . Please name them .

[Old Boggy]

Hi Gunman,

As posted, I have now received further photos, one of which shows the top lever well over to the left indicating much wear and possible further issues. As you say, the information provided is most confusing, not that I`m anywhere as au fait with such things as yourself, but do expect `the trade` to have a modicum of knowledge markings etc. I don`t think that it is a gunshop as such, but trades as `Jeff`s Guns` and was advertising on Guntrader.

I thank you once again for your observations and confirm that in this instance I am going to walk away from any potential purchase.

Also, I appreciate and take an interest in any input that you have on all gunmaking related posts in the past and in the future as you clearly have had much experience in the trade.

Thanks again for your comments.

Kind Regards,

Chris

[Fil]

Sounds like the same dealer that sold a chap on here a 3" 410 but said you can only shoot 2 1/2" through it...lol

[Gunman]

19 hours ago, Fil said:

Sounds like the same dealer that sold a chap on here a 3" 410 but said you can only shoot 2 1/2" through it...lol

Problem is that any one can get an RFD and set up as a dealer . They do not have to show any knowledge of the proof act or firearms law . There should in my opinion be a basic level of knowledge with a exam before any one is allowed to trade .Every dealer should have   bore gauges ,wall thickness gauges, chamber plugs and tables of all proof sizes and marks as a minimum equipment and be able to use them. 

Then that just me .

[CharlesP]

Gunman I so agree with you. 

Cost is probably one prohibitive factor.

Another is the bit about "...and be able to use them".

 

[JohnfromUK]

2 minutes ago, CharlesP said:

Cost is probably one prohibitive factor.

In the grand scheme of things it shouldn't be all that expensive.  Despite being just an interested collector/user I have a bore gauge (does 12, 16, 20 bore) and a wall thickness gauge (same coverage), plus stock pull/drop stick (bit like a giant vernier calliper), and suitable spring balances for weight and 'trigger pull'.  Chamber length gauges (non official) I made myself.

The have been bought either new or second hand over some years, but in total, I doubt they have cost me more than a modest Beretta/Browning shotgun.  Compared to the overheads of running a business, this should be a 'drop in the ocean'.  Adding coverage for the smaller gauges (28, 0.410) does seem more difficult as I don't think there are many tools made for this.  I don't think I have ever seen a 0.410 bore gauge.

I was an engineer by profession, so the use of them came as second nature, but none of it is 'rocket science'.  The fact that some things are metric and some imperial is a continuous annoyance, but then that is the metric system for you!

I do agree that for a person claiming to be a dealer to be able to buy/sell a gun, it should be an essential requirement that they can check the legal proof status of a gun.  I find that 'cast' of the stock is one of the most difficult to measure with accuracy.

[Fil]

31 minutes ago, Gunman said:

Problem is that any one can get an RFD and set up as a dealer .

I totally agree mate. But we also have the shotgun certificate dealers. I have one near me who fancies himself as a gunsmith and does botch repairs for a pittance and deals off his shotgun licence. I have seen some guns he sold were out of proof. The feds know but refuse to do anything about it. It's infuriating. I told my FEO that when my rfd comes up for renewal I'll pass on it and just use my shotgun licence just like the other chap! You should have seen the look on his face.

22 minutes ago, CharlesP said:

Another is the bit about "...and be able to use them".

 

 Some "dealers" near me do not have a bore gauge, let alone know how to use one. 

[Fil]

7 minutes ago, JohnfromUK said:

  I find that 'cast' of the stock is one of the most difficult to measure with accuracy.

Some dealers don't even know what that is. I have had no less than three people in the last few years who wondered why they couldn't get on with the gun/s they bought. 

 When I asked them if they were left handed they gave me a blank stare and said "no... I'm right handed". Apparently the dealers swore blind that the gun was right handed and suited them well. And I'm not talking a bit left handed on an English straight hand stock. 

Anything for a sale eh?

[JohnfromUK]

18 minutes ago, Fil said:

I have had no less than three people in the last few years who wondered why they couldn't get on with the gun/s they bought.

Happened to someone I know - and it was pointed out to him that he had been supplied a left handed gun (a fairly basic Beretta model, bought new).  Anyway, I took a look - and there was indeed a (fairly modest) cast to suit the left shoulder.  When he took it back to the dealer (he'd only had it a week or two), they tried the 'no sir, single trigger guns are suited to both shoulders, that's why they are made like that nowadays'.  Fortunately, the proprietor came in and had more sense than his 'assistant'.  Either the gun or stock was changed (can't remember as it was some years ago) and he now shoots quite well with it.

I have personally witnessed some 'sales pitch', usually offered by young sales guys who have little knowledge that I find very hard not to intervene.  Happily, I now have my 'quota' of guns and the real gunsmiths I visit for the occasional repair etc., knows their stuff and have probably forgotten more than most dealers will ever know. 

[Old Boggy]

It is reassuring to know that there are many on PW who have extensive knowledge of this subject and I bow down to their expertise and advice given.

No doubt, like myself, there are many who put their trust in the trade and to date I have had no bad experiences only dealing with reputable gunshops/gunsmiths. However, this latest enquiry has made me somewhat dubious and it is most disconcerting to find that there are some trading in shotguns who are far less than knowledgeable than they should rightly be. 

Many thanks again for all the interesting and informative replies.

OB

 

[JohnfromUK]

22 minutes ago, Old Boggy said:

No doubt, like myself, there are many who put their trust in the trade and to date I have had no bad experiences only dealing with reputable gunshops/gunsmiths.

The reason I invested in the measuring tools was that at the time I bought my bore gauge (over 30 years ago now) - I had been made redundant and gone self employed contracting (engineering).  Whilst this was 'picking up', I occupied my time in part by visiting some auctions, including some gun auctions with a possible intention of increasing my modest collection.  I had a family friend who was a collector (guns and antiques) and a fountain of knowledge and owned the kit and who was sometimes able to come along and give me guidance.  In the end, I didn't buy anything that way, but I learned that when I was interested in something, the auctioneers had a specialist on hand who would measure the item of interest for you (or in some cases give you measurements that had been taken earlier). 

You could also then buy the 'stock, action and forend' of out of proof guns and have the barrels 'made available' to a gunsmith for sleeving.  I (think I) learned three things in that time;

1. Many of the older guns go to auction because the shops either can't sell them, or they are 'trade ins/hand ins' that are in need of work that would not be economically viable (e.g. are only just in proof, have marginal wall thickness, dented/bulged, badly damaged stock/forend, very loose etc.).
2. That there are quite a few people who know 'a good one' - and the decent guns went for sound prices (it seemed that way then anyway).  I'm sure there were bargains, but none came my way!
3. There were a number of people in the gun trade who were very helpful and friendly towards a novice - and I learned a lot.

Edited January 19, 2018 by JohnfromUK