Reproofing a BPE rifle to NE?

[Daven22s]

I’m looking at a .500 BPE that is stamped “ reproofed to 3250 bar” in 2001. .500 NE are 2800 bar. Does this mean it’s safe and prudent to fire .500NE rounds in it or “nitro for black“ rounds? If I buy it I would hate to damage it but, I have zero interest in using black powder.

 

[Red Leg]

I’m looking at a .500 BPE that is stamped “ reproofed to 3250 bar” in 2001. .500 NE are 2800 bar. Does this mean it’s safe and prudent to fire .500NE rounds in it or “nitro for black“ rounds? If I buy it I would hate to damage it but, I have zero interest in using black powder.

If you reread this thread it should answer your question.

 

[Bob Nelson 35Whelen]

These are the proofs on my newly acquired .577 Greener. Opinions please. Thanks.View attachment 249485 View attachment 249486 View attachment 249487

@Thomas Rutledge
My calculations show the barrels were proofed to 41,480.79 psi if this helps
Bob

 

[rookhawk]

There are many things that determine appropriateness for a particular ammo, in this case a full nitro load.

proofing for that load

Having original barrels of correct weight

Having correct sights for that velocity

Having suitable lockup to handle that loading repeatedly over time

having a sufficient wrist and stock for a full nitro load

***No matter what a proof house determines is safe via proof for a given service pressure like 500NE, it is not a gun designed to handle that duty cycle. 500BPE guns can shoot 500 nitro for black loads at a similar service pressure, but they were never designed for the purpose of shooting a 500NE load.

 

[Bob Nelson 35Whelen]

So the best source of loads I know is Graeme Wright's "Shooting the British Double Rifle" 3rd edition.

For .577 3" Black Powder Express, here is what they have:

Original Ballistics:
167gr BP - 570gr bullet - 1725 fps
167gr BP - 610gr bullet - 1650 fps
167gr BP - 560gr bullet - 1740 fps

Average regulating load:

650gr jacketed bullet - Swiss 3Fg (No. 2) 170gr, Fed 215 primer, Bertram Cases, 1545fps
570gr cast lead - DUPLEX LOAD of 18gr SR4759 Plus and 130gr GOEX 2Fg - WLR primer - Bertram Case - 1590fps

The loads require wads or buffer, plus lube.

For .577 3" Nitro-For-Black Powder, here is what they have:

Original ballistics:
Cordite 65gr - 560gr bullet - 1700fps - 6.0tpsi
Cordite 75gr - 560gr bullet - 2000fps - 8.0tpsi

*That means 8.0 tons per square inch is maximum pressure you should target with a Nitro proofed .577 black powder that has been reproofed for nitro loads if you want to be prudent. A long ton conversion of tpsi to psi is 17,920psi for your pressure target, or 8.0 tpsi (UK Long tons)

Modern regulated loads to accomplish this:

650gr jacketed bullet - H4198 powder - 78 grains - Fed 215 primer - Bertram Case - 1840fps (if it will regulate) Dacron filler.

650gr jacketed bullet - Varget powder - 100 grains - Fed 215 primer - Bertram Case - 1850fps (if it will regulate) Foam filler.

650gr jacketed bullet - AR 2207 powder - 78 grains - Fed 215 primer - Bertram Case - 1840fps (if it will regulate) Dacron Filler

650gr jacketed bullet - AR 2208 powder - 100 grains - Fed 215 primer - Bertram Case - 1850fps (if it will regulate) Foam Filler.


Wadding and stuffing is CRITICAL to these loads. Not using correct wadding or filler can result in damage to gun or personal injury.

None of this is my opinion, don't sue me. Sue Graeme Wright if you injure yourself. (that's the legal disclaimer there at the end)

@rookhawk
Using a slower powder such as H4831sc will fill the case more while giving lower pressure at similar velocity with out the need of fillers
Bob