Can someone help me in using jacket bullets in a 7mm Remington Rolling Block. Have bullets from 120 gr to 175gr.
Powders, H4895, H335, RELOADER 19 AND IMR 4198 if any of these will work?
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Can someone help me in using jacket bullets in a 7mm Remington Rolling Block. Have bullets from 120 gr to 175gr.
Powders, H4895, H335, RELOADER 19 AND IMR 4198 if any of these will work?
The first thing I would do is measure your throat length. If your 7x57 Roller is anything like mine you'll find it has an extremely LONG throat (and possibly a very long chamber too). To fit my cases to my Roller I expanded the neck up to about 30 calibre and then slowly ran it back into my 7x57 fl sizing die turning the die down about 1/8 turn at a time until the block would JUST close and the hammer would drop when the trigger is pulled. The chambers on these old military 7x57 Rollers are often not standard to the current SAAMI specs on the 7x57 Mauser cartridge. They also tend to be a bit fat (like most military rifle chambers) and will likely give you some fat based fired cases. In my 7x57 Roller I stuck with 175 grain bullets to keep them as long as possible since even seating them WELL out of the case mouth they still aren't anywhere near touching the throat. (Photo below to show you how far out I have to seat mine.) Mine shoots very well with 34.0 to 35.0 grains of either IMR3031 or IMR4064, but since individual rifles vary greatly (especially individual military rifles with typically wonky chambers) I'd start down at about 32.0 grains of either and work up slowly watching for case expansion at the bases. Keep us posted and let us know how it works out!
https://i.imgur.com/OH0CAEA.jpg
PS: Some folks have had good success reforming and shortening .30-06 cases for these old Rollers, especially using military .30-06 cases. They form them to match the chamber in the individual rifle since most are long on shoulder length and long on case length compared to modern production 7x57 brass.
Any safe loads for the powders I listed ?
I had a no. 5 RB in 7 mm and used H 1000 powder with a 175 gr. J bullet.Quote:
Originally Posted by brstevns
I would think you could use R 19 without getting to high of pressures.
I have some Alliant data showing a load of 48.3 grs. of R 19 with a 175 gr. @ 45.6 K pressure.
I wouldn't load it to that level but maybe reduce it at least 10 % and try it at 39 - 40.0 grs and inspect the brass carefully.
Your on your own really as most load data doesn't list pressures for starting loads but the R 19 is the slowest you have and with jacketed bullets probably the best.
Alliant has Technical Assistance, call them at 800-276-9337
Jedman
I got my "pet load" of .35.0 grains of IMR4064 from the previous owner of my 7x57 Roller and even though it has a well worn barrel it shoots so well with that load that I really haven't tried much of anything else. I only tried the IMR3031 load since I couldn't find my tin of IMR4064 one day and worked up a similar load with it as well. And again, I'd definitely want to keep the pressures to very moderate levels in these old rifles just to be safe, and I like to use the medium to slower burning powders to help do that. If I wanted a "hot rod" 7mm then I'd buy a 7mm Remington Magnum in a strong bolt action, but since I don't hunt anymore thanks to multiple ongoing health issues now I just enjoy target shooting up at our local range with these old, vintage guns instead.
Quote:
Originally Posted by brstevns
I have used IMR 4895, 4064 and 4350 and I keep the load down to 80%-85% of maximum and using J's up to 175 gr in wt....that being said the action on my RRB is very good and tight
I also re-form GI brass to 7x57 as it works well in my rolling block
The action on mine is very tight and the bore not bad. I will have to fire form the brass or expand it up to 30 cal and keep sizing it back down till block closes . Might try to make some by using 270 win and 30-06 and a RCBS form trim die. If fire forming would 5gr Bullseye and fill the case with cream of wheat work ?
After neck expanding and then resizing until there is light resistance to closing the action I didn't bother to fire-form with blank charges and filler. I just loaded them with the data that I had been supplied with for my rifle and then fire-formed the cases shooting those "full" loads.
I would caution against full sizing until you do a test piece, one or two rounds. Mine head separates on 3rd full size. Not a safety issue, just costly keep us posted.
Plan on just neck sizing after first firing.Quote:
Originally Posted by ascast
I've been wanting to try some suitable boolits in mine. Got some 175 grain GC Lyman #287308's from a friend and they look like they'll be perfect for my old South American 7x57 Rolling Block. So I though "Where am I ever going to find a copy of this now discontinued mould for myself?" Went poking on eBay with no luck. Threw a wider Net (literally) and low and behold a fairly close vendor to me had a lightly used Lyman 4 cavity #287308 for sale on consignment! Just arrived in the mail ...
:smile:
Have you been able to try them ?Quote:
Originally Posted by Reverend Al
Unfortunately no ... things have been on hold for a while since my wife had a knee replacement surgery about 5 weeks ago. Been sticking close to home playing "house nurse" and haven't been up to the range to shoot at all. She's improving so hopefully I can get in a range day in the next week or two ...
I know what that is all about, My wife has had both her knees replaced. One knee twice and the other three times!!!Quote:
Originally Posted by Reverend Al
In my 7mm RRB, I have used 36 grains of H335 with 140 to 154 grain jacketed bullets. With a slower power like H414 try 38 grains with bullets of the same weights.
I use 270 WCF cases resized, trimmed and annealed, and once they are fire formed, only neck size. Case life runs from 3 or 4 reloads to 7-8 depending on all the usual variables. After firing, check the inside of the cases for thinning at .25" above the extractor groove. I made a tool for this out of coat hanger wire with a slight bend near the end and a sharpened tip. This tool was a left-over from reloading for a #1 Mk III* SMLE which also had a generous chamber.