Used small arms, particularly shotguns, may appear properly proved and marked, but may have been weakened and the proof marks rendered invalid, by enlargement of the bore to remove rust or pitting or by other material alterations. This is not uncommon. Special equipment and knowledge of the subject are necessary to determine whether proof marks are valid or otherwise.
The advice of the Proof Authorities as to the disposal of guns bearing proof marks, where barrels are beyond repair, (and it is understood that this is already the practice in many auction sales specialising in arms), is that the stock, action and fore-end may be sold, but the barrels may not.
Where the barrels are repairable and can be reproved, this must be done prior to sale.
A certificate is available, on payment, from either Proof House for guns which are not to be used, as for example antiques or collectors items, which cannot be proved, as where no ammunition is available.
An increasing number of complaints is being received, of the unlawful sale of small arms at auction - at times in condition dangerous to the user. Recommendation is made that auctioneers take expert advice before offering small arms for sale. The Proof House will give every reasonable assistance but must warn that they will institute proceedings where offences are considered to justify such action. The auctioneer, the owner of the arm and the person submitting the arm to auction bear equal responsibility at law.
The purchase of a second hand shotgun involves somewhat similar risks to those incurred in the buying of a second hand motor-car, or an expensive second hand watch. Each to a degree is the product of skilled craftsmen, and in none is it a simple matter for the layman to detect every defect or weakness.
To suggest that one should go to a reputable gunsmith or dealer and buy the best gun one can afford may be sound advice, but it is cold comfort to those who really cannot afford a good second hand gun or to those who may be tempted to purchase a second hand gun from an acquaintance, in the market place, at auction or sale room or even at the local tavern.
When contemplating the purchase or sale of a used gun, check must be made that the proof marks remain valid. Proof marks indicate the soundness of the gun when it was last proved, but the gun may have been so altered that it is unproved in its present state, although the proof marks remain.
The incidence of VAT on new guns added to their already high cost. This has placed a premium on the better class of second hand guns so that there are many cheaper, old guns being offered for sale, which in more normal times, would have been considered past further service.
Where purchase is contemplated from sources other than reputable gunmakers, gunsmiths or dealers, it is suggested that the gun be submitted to a reputable gunmaker for report on its condition prior to completion of the transaction. Where difficulty is experienced in obtaining such a report, request may be made to one of the Proof Houses for advice as to whether or not the gun is or is not in a fully proved condition. However, the Proof House should not be expected to advise as to mechanical condition, quality or value.