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I am away on vacation and so do not have access to my files and drawingsbut An original M1 or M1A1 bolt is so hard a file will skid right off and not cut. Buried in Dougs papers I can probably find the alloy of steel used, but in the WW2 era the Ordnance Department did not use the Society of Automotive Engineers (SAE) steel numbering system. 4140 is an SAE steel. The steels called out on Ordnance drawings have a WD prefix which stands for War Department. I have been on the lookout for a conversion chart for SAE/WD and have not found one. But I think the reason for the WD steels is that they have tighter alloying specifications than the SAE steels. Maybe this is why there is no conversion chart. A hardness of Rockwell C32 is nothing. If that value came from checking a Thompson bolt there is a mistake somewhere. If a bolt is only C32 it could be easily filed, hacksawed, etc. and would not hold up to the hardened sear. Thompson bolts are probably RC 58-60 which puts them at the low end of case hardening. The M1A1 bolts we (Phila Ord) make are machined from stress relieved 4140 which is hardened as high as we can go with 4140 which is around RC 54. We do not case harden the bolts to get up into the low RC 60s because we have not been able to do that without the round bolt head warping and bending. I have made and sold around 150 4140 M1A1 bolts and they seem to holding up just fine. Getting back to the original question if your bolt is RC 22-25, its not hardened at all. I dont get it. The raw 4140 steel we make the receivers from is probably around RC 18-20 which is so soft the steel supplier gives the hardness on the Brinnel scale. (HB 180-220). So if your bolt is that soft something is wrong. I guess you could keep using it but you should really find a correct bolt. Thompsons are pretty indestructible. A few years back we had a post sample (07/02) that was a rental range gun and the guy sent it to be rebarreled because the barrel was shot out. I asked him how many rounds thru the gun and he said 50,000+. I was looking forward to seeing the effects of s well documented 50K rounds. The gun got here and it was pretty dirty but when we cleaned it up it looked like it had 1000 rounds thru it - not 50,000. All of the parts in the trigger frame and the bolt had almost no wear. Bob

Another Irish Sword. No idea on the serial number though; I spoke with the docent in the office next to the display and he had no idea either. Regardless, this one is on display at Caernarfon castle in Wales, in the Welsh Fusiliers’ museum as part of a display of weapons seized from the IRA.

I noticed The Ultimate Thompson Book (TUTB) is no longer listed for sale at the Collector Grade Publications website. I suspect it is now officially out of print. Tracie still has copies available and I would guess there are a few copies with various booksellers across the country. There is little doubt it will become hard to find as time moves on. Remember the price increase of American Thunder II when it went out of print prior to the release of American Thunder III. TUTB is a must have book for every Thompson enthusiast.