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RC35 harness Caspian slide… too soft?

259 Views 6 Replies 4 Participants Last post by  JoeyMac
So my slide showed up for my first ever build. A Caspian .40/10mm carbon slide with ball cuts and reverse plug. Inspection tag shows a 2016 mfg date (obviously new old stock) which is just fine considering it was $200. The other thing that caught my eye on the Caspian inspection tag was the hardness listed at RC35.

I thought most slides were supposed to be RC37–42. Even thier own website says:
“Our forgings are made in the USA with USA material of certified 4340 hi-carbon steel or 416 stainless steel. They are struck on Caspian dies and pre-heat treated to 37-41 RC before they ever see a…”
Is this an issue or should I be worried? If so, is it even worth talking to Caspian on a slide built 6+ years ago? Will I have to be careful that the frame I get for this slide is still relatively soft enough? This is ultimately going into a 10mm CCO build … so a pretty demanding build as far as 1911 stress goes.
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Why don't you quiz them as to why your slide doesn't meet the criteria you purchased it under, and as such it will be under somewhat severe service .. check their reaction/explanation first.
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What he said ^^^^^^^^^^^^^^^^^^^^^^^^^
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I could do that. Is there a standard I can reference when talking to them? Aside from assurance or guidance, I really don’t expect them to do much warranty-wise for a 6+ year old part from a third party vendor (I got it at Brazos Customs). I mean, it has an inspection tag plainly stating the hardness… if that was concerning it shouldn’t have passed QC, no?

I just wanted the opinion from guys that do this for a living if a 35RC slide is something that is any way concerning.
Well I called anyways and they said it shouldn’t be a problem for even for a 10mm build.

so on the bright side… it’ll be a little easier to machine and cut serrations into than a 40RC slide if nothing else. 😅
The whole slide is not at the same hardness. Most frames top out at around Rockwell C 32, so a slide that is at C 35 on the bearing surfaces for the frame should be fine even if it is not as hard as I may prefer. Below is an old drawing that shows where the slide needs to be harder, namely the notches for the slide stop, the thumb safety, and barrel lugs. That slide may be a good candidate for a nitride finish that will harden the surface of the part while making it more corrosion resistant.

It is also important to not confuse hardness with strength.
White Rectangle Slope Organism Gesture
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I considered that and actually live about 15 minutes from H&M Metals. They’ve done cash-jobs for me before. But I’m trying to do everything (optic cut and all) on my own, if I can. I’m planning on a molten kno3 salt finish at home (nitre bluing).

if I did send it out finish, I’d probably do a blackened slide over a chromed frame.
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