Pedersoli Proof Test Rules and Allowable Limits

Many BPCR owners are concerned about the safety of original and replica rifles. Of course an original should be examined by a gunsmith who is familiar with such arms and who is competent to pronounce the arm safe or unsafe. There is always the temptation to try and shoot an old gun which may have been in your family a long time or which you recently obtained. In most cases it is safe to fire such an old gun using the correct black powder and bullet weight but the following advice should be considered first.

Certain types of steel alloy used in original guns of the BP era may have changed over the 100+ years of time. Once safe guns may now have internal cracks or molecular flaws which have developed over such long time periods. Age alone may have made the steel become "brittle" and unable to withstand ignition pressure safely.

Therefore, even though the exterior of a gun may look normal, there could be serious problems within the barrel and action which might cause a failure when even a "normal" powder charge is fired.

As a basic guideline.........when loading "full case" charges of the correct grade of BP behind a bullet of normal weight for that caliber, you will not exceed a pressure of around 22,000 to 26000 psi (or CUP) and modern made replica guns can handle such pressures safely. Use of a heavier than normal bullet or a black powder grain size which is too small in size, will cause higher than expected ignition pressures.

Original BP guns with internal flaws or replica guns which may have been repeatedly fired with excessive pressures in the past, may fail even with a so called "normal" load.

Original antique firearms have the best steel available at that time but today we understand more clearly that the old time steel contains various impurities and inclusions which after more than 100 years, can cause internal weakness and flaws which could cause the gun to be unable to safely handle it's normal chamber pressure. To avoid damage to the old gun as well as preventing injuries to the shooter or bystanders, it is suggested that original antique guns be fired only with reduced or mild charges……. after having been inspected by a qualified gunsmith.

The situation is quite different when smokeless powders or a "duplex load" having both smokeless and BP is being used.

Really dangerous and destructive pressures are easily produced which can result in damage to the gun as well as injury to both shooter and bystanders.

Because of the dangers mentioned above, and the fact that no one outside of a testing laboratory or proof house has the proper equipment to measure the pressure and strain produced by any ammunition, the Pedersoli company states that their cartridge rifles are to be fired only with "commercially produced" smokeless powder ammunition or, with black powder ammunition which meets the pressure limits set forth by the European C.I.P or American SAAMI organizations for each caliber or cartridge name.

Pedersoli & Co. like all Italian firearms manufacturers, is required by law, to have every firearm proof tested at the Italian National Proof House in Gardone Italy.

Many other European gun makers also send their complete gun or barreled actions to this same proof house when there is no similar proof house in their home country. Buyers look for proof marks as an assurance of safety and quality so manufacturers pay the extra price to have guns proofed by a recognized govt. controlled proof house.

Below is a copy of the standard letter Pedersoli provides to customers who ask about the proof test pressures for their Black Powder Ctg. Rifles.

It should be noted that in the USA, Federal or State Law does not require the proof testing of civilian firearms and there is no national proof house in the USA for such testing.

Only military contract firearms receive high pressure proof testing under strictly controlled conditions. All other firearms may or may not be proof tested by the manufacturer in some manner and if proof testing is performed, there is no government supervision or control so the customer must rely upon the manufacturers’ reputation in regards to the firearm strength. Fortunately, even though commercial firearms made in the USA do not have proof testing marks they are found to be strong enough for commercial ammunition made according to recognized SAAMI pressure ratings and the customer relies upon the reputation of both the gun and ammo manufacturer.


All Pedersoli rifles are proof tested at the (Italian government) National Firing Proof House with smokeless powder cartridges with a pressure exceeding that of the ‘commercial’ factory made ammunition by 30 %.

For the .45-70 caliber we normally recommend the use of commercially made ammunition because of it being easily available on the world market. We show here some warnings about C.I.P. rules:


Our guns are proof tested according to the rules imposed by C.I.P. (International Proof Commission). Proof test pressure is 30% stronger than the maximum pressure of a commercial cartridge (Pmax.) Pmax pressures are measured in BAR units.

The below mentioned data are compared to the Crusher (CUP) and PSI method.

The equivalent maximum pressure value of the commercial cartridges measured according to the English/American P.S.I. and C.U.P. system is obtained by multiplying the BAR value x 14.5037.

The list below represents the maximum pressure to be developed by a commercial cartridge to be used with our guns, in the various calibers shown .In no case should the cartridges exceed such pressure values.


Smokeless Powder Cartridges




30-30 Win.



30-40 Krag



38-55 Win.



357 Mag.



45 Colt



45-70 Govt.



8x57 JRS







Black Powder Cartridges                    




38-55 B.P.



40-65 B.P.



45-70 B.P.



45-90 B.P.



45-100,110 B.P.



45-120 B.P.



45-70 Light B.P.


18000 (**)

50-70, 50-90 Light B.P.


18000 (**)

50-70, 50-90 B.P.


25000 (*)



These calibers with B.P. indicate the use of commercial cartridges cases reloaded with BLACK POWDER only.

(*) This pressure is allowable for modern made Pedersoli rifles in 38-55, 40-65, 45-70, -90, -100, -110, -120, 50-70, and 50-90. It may not be safe with other brands of replica arms and those mfrs. must be consulted for their data.

(**) This pressure is generally considered to be near the safe limit for original antique Trapdoor model rifles which have been examined by a qualified gunsmith and found to be in good condition. Modern made Pedersoli Trapdoor 45-70 rifles are safe to the higher 29007 PSI/CUP pressure. Other brands of modern made Trapdoor rifles may not be safe at this high pressure and the mfr. must be consulted for their data.

The modern replica Sharps, Rolling Block and Trapdoor models we produce are stronger than their original versions due in part to improved steels as well as minor changes made to strengthen original design weakness and add some discrete safety features. Although it is unpleasant to shoot maximum pressure loadings, we do permit the use of ammunition which does not exceed 29007 psi or CUP in these BP Ctg Rifles, regardless of their caliber. This allowable maximum pressure may be obtained using either black powder or smokeless powder loadings.

When using smokeless powder it is the responsibility of the reloader to use only the correct type of powder as well as the correct weight of powder in conjunction with the type and weight of bullet being reloaded.

Use ONLY the printed reloading charges listed by the powder manufacturer and which show the chamber pressure for each such reloading combination.

We recommend the Accurate Arms reloading book #2 (phone 800 416 3006 ) as meeting all our requirements for bullet types, pressure readings and powder charge selections.

Other powder and bullet manufacturers books are equally recommended if they list all the required data.

The Pedersoli company assumes no responsibility for injury or damage caused by firing ammunition loaded wrongly or to excessive pressures.

We are aware that there is smokeless powder 45-70 cal. commercial ammunition being sold which advertises pressures of 40,000 psi and we advise against use of this type ammunition. The large capacity thinwall brass cases are not designed to handle such excessive pressures and will have a very short reloadable life and may burst when fired at such high psi. For "ALL" large case black powder calibers, the best accuracy is obtained by the use of carefully developed loads using blackpowder and cast lead bullets in a bullet length suitable for the barrel twist of your rifle.

For Davide Pedersoli & Co.

Dick Trenk
Competition Events Coordinator

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