Excerpt from the reply letter from Parker Brothers to Capt Charles Askins:

“Replying to your letter of December 17th [1920] …... Referring to the cone, we ordinarily permit our shells to lap into it 1/8-inch but as a matter of fact we have found that the majority of guns will shoot a better pattern with even more lap than this. …… In user’s hands we do not advocate the use of longer shells than those which give 1/8 lap.

Parker Brothers, per W. A. King”

The chambers in my 1898 DH 12 with Titanic Steel barrels are 2 9/16” and when I shoot 2 3/4” AA’s in it the very tips of my fired shells are pinched… even to the extent of being pinched off. The felt recoil is only a smidge more than when I shoot 2 1/2” shells of equal loading.





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Would someone 'not from around heuh' understand this?

Hmmm…

How about an increase in felt recoil of .017 ft. lbs. ?





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Are we really to think that 2/16" or even 3/16" encroachment of thin plastic into the largest end of a tapered forcing cone would have any effect at all on pressure? I'm going with "I don't think there is any effect on pressure whatever".































































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Photo 1 is from DGJ, referring to a preceding article mentioning 300psi as a common pressure rise.

If a person has a gun that is on the edge of decrepitude , I suppose a 300 psi rise might be too much.

The next 2 photos are from Parker brochures .