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Gunplummer · May 22, 2015, 01:35 PM

Pretty long winded explanation, but it does point out that SAAMI gages are not EXACTLY compatible to MIL-spec or European spec chambers. I have never shot a 1917 Enfield, .303 Brit, or 30-40 Krag, ect. that was not hard on American civilian brass. If I remember correctly, most body diameters on the SAAMI spec case are about +.008. I have found Winchester brass to be on the low side out of the "Big three". It can look pretty ugly coming out of a 1917. On the other hand, military brass is a lot thicker and can cause issues in SAAMI spec rifles.
I have no idea why someone would experiment lengthening the front of a chamber. Putting a shorter cartridge in a longer chamber is a pretty common occurrence. I accidentally did it myself once. The wrong case assumed the dimensions of the chamber, including swelling tremendously right in front off the head. Just a guess, but I believe the brass outruns the bullet in instances like this. If the man wanted action, he should have increased the distance between the case head and bolt face and used a longer firing pin. Hey, wait a minute! Is that not the Original Poster's point?

May 22, 2015, 01:35 PM	#104
Gunplummer Senior Member Join Date: March 11, 2010 Location: South East Pa. Posts: 3,364	Pretty long winded explanation, but it does point out that SAAMI gages are not EXACTLY compatible to MIL-spec or European spec chambers. I have never shot a 1917 Enfield, .303 Brit, or 30-40 Krag, ect. that was not hard on American civilian brass. If I remember correctly, most body diameters on the SAAMI spec case are about +.008. I have found Winchester brass to be on the low side out of the "Big three". It can look pretty ugly coming out of a 1917. On the other hand, military brass is a lot thicker and can cause issues in SAAMI spec rifles. I have no idea why someone would experiment lengthening the front of a chamber. Putting a shorter cartridge in a longer chamber is a pretty common occurrence. I accidentally did it myself once. The wrong case assumed the dimensions of the chamber, including swelling tremendously right in front off the head. Just a guess, but I believe the brass outruns the bullet in instances like this. If the man wanted action, he should have increased the distance between the case head and bolt face and used a longer firing pin. Hey, wait a minute! Is that not the Original Poster's point?