284 Win to 7.5 SR

[Duckiller]

Some where I read that it was easy to convert 284 WIN to 7.5 SR. Is this true? Using a SR shell holder I stuck a 284 case in my SR di. Took awhile but I did manage to find my stuck case remover tool. Will use the 384 shell holder to expand necks to SR diameter. Is there anything else I should be aware of? I do have proper sized Berdan primers but they are a real pain to remove with water in the case. Don' mind Berdan primers for hunting loads but want to use Boxer primers for target/plinking loads. Any and all advise is welcome.

[EDG]

Use a .308 shell holder with .284 brass.

[Kraschenbirn]

I've reformed a couple hundred rounds of .284 to 7.5 Swiss in one pass using RCBS 7.5x55 dies. Using new brass, I didn't even have to anneal the necks. However, as you found, you need to use a #2 shell holder (.308/.30-06, 243, etc, etc) rather than the #3 that comes with the dies. On the other hand, Grafs has Boxer-primed Privi 7.5x55 in stock at a LOWER price than Win .284. Also, while I've found that reformed .284 works just fine in a couple of K-31s, my G96/11 doesn't like it at all...extractor won't hold on the .284's .022" smaller rim.

Bill

[SOFMatchstaff]

[QUOTE On the other hand, Grafs has Boxer-primed Privi 7.5x55 in stock at a LOWER price than Win .284.

Bill[/QUOTE]

this was my initial thought, but you covered it. Making cheaper brass from expensive stuff, plus the effort, to get an out of spec finished product. I was considering making 475 Wildey from 284, but the math said buy the Starline pistol brass at $.25 cheaper than the 284, plus the cut, trim , ream operations. I like this stuff, but not that much.... then again if you have a butt load of free brass, it might make more sense..

[Duckiller]

Thank everyone for the help. Got the stuck case out of the di and expanded some more cases. I am working with 284 brass because I bought it several years ago and had done nothing with it until recently. I will load some small number of cases to make sure my 1911 likes it. If not then I will have to buy 7.5x55 brass.

[Duckiller]

Now I have a problem with 284 brass being resized to 7.5x55. 284 brass will not chamber. I think that it is the body that is too large. Ran some cases through a 7.5 RCBS di and that won't chamber either. The resized brass goes into the chamber farther than the284 brass but is still about 3/4 to an inch from completely closing. Any ideas other than giving up and buying 7.5 brass from Grafs would be greatly appreciated. If this doesn't work out Iwill probably buy some brass from Grafs.

[Wayne Smith]

Difference in the dies. I think it is the Hornaday (and maybe Lee?) dies that are cut for the K31 chamber which is tighter than the earlier chamber.

[Kraschenbirn]

Hmmmm…didn't experience anything like that using my RCBS dies for resizing .284 Win to 7.5x55. Rolled .284s on a felt pad with STP, swabbed inside of case necks with a q-tip dipped in powdered graphite, and ran them full-length thru the dies. Fire-formed with a light charge of 2400, trimmed necks, and never looked back. Cases chamber easily in both K-31 and 96/11 (but, as mentioned earlier, the 96/11 extractor doesn't get always get adequate engagement on the .284's small dia. rim).

Probably doesn't matter, but do you have any idea when your K-31 was manufactured? Mine is pre-WW2 (1937 s/n) and was issued to a corporal from Neuchatel in May of that year whom I suspect may had had it for his entire military service. (His original fountain pen-lettered card was under the buttplate and, had the rifle been turned in and reissued, the next guy most likely would have replaced it with his own. According to the Neuchatel city records, a person of same name, born in 1912, passed away there in 1978.) My gun has been well-maintained but does show wear...some throat erosion, cosmetic dings, etc...a post-war barrel could have been manufactured on improved tooling with tighter tolerances.

Bill

[Duckiller]

My gun is a 1911, between the 96/11 and the K31. Bubba may have worked on the stock. Called RCBS and their tech said St6art with the di flush with the shell holder and the lower the di 1/8 to 1/4 turn. Did it but maybe not exactly right. Will try again following instructions exactly. Then I am going to smoke a case and see where it is hitting. Probably should give up and buy SR brass. Not going to shoot it a bunch but would like to hunt deer with it. After smoking will repost again.

[Duckiller]

Have ried redoing the resize and smoked brass. Brass may be slightly too long or too fat. Anyway it won't chamber. Time to buy some 7.5x55 brass.

[frkelly74]

As said before it might be the die set you are using, in which case the new brass will eventually not chamber either. I seem to remember that Redding dies (yeah the expensive ones) were cut to correspond with the 1911 chamber dimensions. I would be happy to send you some cases that I have resized with my lee dies and you can see if they will chamber. One thing that has caused me to have chambering problems was caused by over crimping the bullet which will distort the shoulder of the case enough to prevent chambering.

[17nut]

I have a G11 (from '18) and uses Lee dies with good result.

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[RangerDan]

I've been using the Prvi 7.5x55 brass for a couple years and it is good stuff. It has worked in three rifles without a hitch. I'm on the seventh loading of some and no sign of them wearing out.

[Duckiller]

My resized brass works great in the LGS' K31. It will not chamber in my 1911. Will have to buy some brass from Graf's.

[17nut]

Have you tried the Sharpie treatment and see where the problem is?

Had a 270WSM that would not chamer resized brass from another rifle but virgin was fine.
At some point i realised i used a RCBS shellholder and Lee dies. I ground a smidgen of the bottom of the FL sizer and hey presto!