Is anyone aware of a rimmed version of the 7.5 x55? Been through all my reference materials and can not find any mention. Reason for the question is that I have a Swiss Martini that appears to be chambered for this round. New cases fit the chamber but the extractor does not engage the rim/extractor groove. Have checked and it is not broken just short.

Steve in Oz.

Might have solved the problem. 

If you pull the lever down gently, as I was doing the case seems to bypass the extractor. However, if the lever is forcefully opened the case extracts, ejects and clears the action. Might be different with a fired case but hope to find out on the weekend. 

Initially I will be using Black Powder just to make it go bang. 

Steve

I have two 7.5 Swiss Martinis. one in the GP90 and the other GP11 chamber. 
both are amazing accuracy. 

I shoot a breech seat  modified .325 base dia 32-40 bullet in the fat GP90 ! 
the GP11 likes the NOE k31 Bullet.

Thanks all for the insight.

Used a conservative load of Australian AR2207  (4198 equivalent) with some hard cast, powder coated 165 gr projectiles I purchased for my Sako A1 300 AAC bolt gun. 

1. Had no issues with extraction and many cases flicked completely out of the action.

2. Extracted case suggest it is for the GP10 shorter round. so will do some case trimming.

3. Very happy with how it shot, given the Serious Wild asses Guess (SWAG) that went into the initial conservative load. 

4. Will move the seating depth out (once cases trimmed) and play with the load and will try some AR2205H (4895) to fill the case a bit more.

5. Wish I had better eyes to see the sights better!! 

6. Used PPU cases and Rem 9 1/2 primers as the PPU cases were all that I could find out here (only in one shop with in all of Aus and top dollar, but. will never need any more!). May buy some Norma cases if they turn up anywhere here in Oz.

7. Will post both my 50m and 100m targets later for those that are interested. Please laugh at the results but I'm happy!

Finally, shooting this rifle is part of a plan I set myself for this year. I am in a fortunate position to have a reasonable number of rifles (mostly inherited from my old Dad) and I am trying to shoot a different rifle each week. This should see me through to the end of the year (not all single shots BTW, but mostly). Part of this means getting cases, sorting loads etc. which, I think, is the fun part.

So, I have a lot of guns, none of which I shoot well, but do I have a lot of fun! 

Will put up a different post with the guns I shoot each week purely for interest.

Cheers Steve in Aus. 

p.s. Any comments for Gumpy out here in Aus should be completely ignored 

Would love to hear a weekly report.

If you are as young as the rest of us, a couple of years short of a white stick, with the open sights in the photo, those are quite acceptable for the first time out.