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Frank, This business of searching even fairly recent loading manuals can be rewarding, as well as missleading. For example; Lyman 47 page 263, 30 M-1 Carbine. IMR 4227 13,5 gr 110 gr Jacketed RN 1642 fps 28.200 CUP. 32-20 case is about 10% larger than 30 Carbine and I only get 1550 fps from 13,0 grains, weighed on verified powder scale . Rough estimate for my old rifle would be maybe 20% below that pressure which is 22560 CUP, only considering differences in case volume and 10 grains less bullet weight. Add in the 0,5 grains less 4227, if you want, to get even lower estimate of chamber pressure in my old rifle. Furthermore, I am shooting a 0,312" Hornady XTP bullet down a 0,313" bore. A bore that starts at 0,316" and over several cm gets to 0,313". Hardly a means of increasing or even maintaining chamber pressures. Frankly, I am surprised that I get such nice 100 yd groups as I do. But, such much improved group sizes have been reported often for mantled bullets in ratty old 32-20 bores. Actually, every since I was 13 year old, with another old Win LW, I have been told that by same gunshop/gunsmith that got me into loading my own BP ammo for that rifle. That ratty bored rifle took 50 original HV load with 80 gr 2000 fps over several years, killing numeous foxes, etc. Also no loosening of breech block or increase in headspace seen with gauges. Note that those 30 Carbine data referenced above are reported to be with 0,308" bullet in a 0,308" bore. No change in headspace seen, fired primers remain flush with base of cases. Cases extract easily. Case life appears to be good, with at least 5 loading per case for cases used in load development. Breech block is tight fit to back of barrel and base of case is almost touching face, as it has been for over 10 years. Thanks for your concern and attempts to make rational arguments. However, given the apparent difference between conditions for loading data for new, tight bores, and smaller 30 carbine case and performance in my old rifle, I will continue to use this load for the very limited hunting it is used for. It will not used for many shots per year, in any case. Presently, this load is only to be used for 10-20 more "1st shot from cold, dry bore" and hopefully only 1 shot for this year's turkey. Thanks! Den SKG:en
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