Anyone know how hard (Rockwell) a BHP's frame is supposed to be?

Unofficially mid fifties sounds about right to me as well, but I'm not going to go rockwell test my hipower to find out. Mid to high 50s is right about the proper balance between toughness and strength for most steels.

Doing a rockwell test should be fairly cheap and quick. You just put the part on a testing machine and a second later you're done. It does leave a mark since you are driving a small penetrator into the surface of the material. Not sure what the usual price is, but it shouldn't cost too much. Pretty much every mechanical engineering school has testing machine lying around in the material science lab. I'd imagine a decent machine shop would have something like that too to check part temper as well.

One minor issue, depending on how things were tempered and the type of steel, hardness may not be uniform across the part. So if you test far away from the slide stop, you may not be getting a good number.

I don't know about Browning copies, but Caspian and most other 1911 slides are around RC 40. Receivers are softer. I doubt anybody is hardening guns above RC 50 or even close to it.

They'd never make frames at 50+ HRc. 40 seems about right. There are frames and slides now that are case hardened which would reach 50+ such as Glock [Tennifer coating] or HK etc.

Oh btw my estimate was based on blade hardnesses for swords not guns. A good spring tempered sword should be in the mid to high fifties. Its quite possible that guns are tempered lower so they damp out vibration better.

You should go inquire over on fnhipower.com

I vaguely remember the forged frames coming in at around 50 on the Rockwell scale and the cast frames coming in a little higher.

Send me a frame and I'll put it on my Rockwell tester.

- Chris

I doubt anybody is hardening guns above RC 50 or even close to it.

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Thus spake S&W:

Drop forged from solid stainless steel, and heat treated to an incredible Rockwell 70C surface hardness using the Melonite® process, the 5906 Military pistol is extremely durable, and almost impervious to corrosion, surface wear and scratches.

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Melonite is a modern equivalent of case hardening. They are reading Rockwell **superficial** hardness of a surface layer a few thousandths thick. The base metal is much softer.

A Rockwell hardness test leaves a little ding in the metal maybe a millimeter diameter. There have been guns and knives that proudly advertised where to look for the mark to prove 100% inspection.

I have read that even real BHPs are rather soft compared to a Colt. Don't expect a clone to be tool steel. You are paying for the peening with the bucks you saved.

Rockwell 50C is pretty hard, and I don't know many pistols that have frames that hard. (Note that the S&W ad says "surface" hardness, which means essentially case hardening, very scratch and wear resistant, but not resistant to peening. Try hammering on an old S&W revolver hammer and you will see what I mean.)

I have no hardness figures on the FEG, but most European pistol run 35-40 Rockwell C. But, as noted above, the test measures surface hardness, which is not the key to resistance to pounding; overall hardness (and design) is.

From what I see in the pics, there are two problems. The left front rail is peening from the slide striking it. Unlike the M1911, the BHP slide impacts the frame directly rather than impacting on the recoil spring guide. I suspect that the left rail sticks out a bit beyond the lower part of the frame cut and/or beyond the right side rail. I think that peening might be self correcting once the left rail is down to where the slide impact is more evenly distributed.

The rear rail is apparently being hit by the lower rear of the sear lever. That is normal (that is why the slope on that rail), but in your case it could be excessive due either to the lever being too big and not retracting enough, or too long and staying on the trigger lever too long. The sear lever also might not be pivoting as easily as it should.

HTH

Jim

Regrettably, the GP35 serves as a prime example of a great firearm design compromised by manufacturing shortcuts. I would much sooner pay the 300% custom gun premium tacked onto the basic M1911 by the likes of SVI, Les Baer, or Ed Brown, for a pistol that captures the lifetime of John Moses Browning's learning through experience.

I have nothing but good to say about my Browning MkIII. Never a hiccup, and the trigger has become sweeeeet.

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A trigger action that "sweetens" in use is a telltale sign of soft steel liable to peen and loosen up elsewhere. I've had a SIG P210 trigger pull stay constant well into tens of thousands of rounds. A GP35 made to the same quality standard would be a formidable weapon. The FN product is no such thing.