My SMLE (1917 Enfield) always leaves a slight bulge in the back end of the case, head space is fine.

The SMLE had a rather generous chamber, apparently configured to facilitate the Rifles reliable use in 3 feet of mud during WW1.

I can only assume that Ishapore kept the same chamber spec?

My No4 and No5 far less so, with a very slight, barely noticeable deformation.

I would concur regards recoil, .303 is certainly a lot more sedate than .30-06.

I notice the same thing when I switch between my Enfields and my A4 at the range.
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