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View Full Version : Old pro's and new guys , a cautionary tale of reloading.



Harter66
08-29-2018, 10:13 AM
I've been a party to reloading since the Herters catalog was a staple and Cabela's had 2 stores . I've lived in the golden ....at the trailing edge of the wild cat Glory days . I actually got to shoot a pre-308 Winchester .....well 308 Win .... Dad's 25-06' is one of the very early Rem production rifles and that and Model 12s is where I started .

I started casting in 2007 and moved into cast in rifles in 2010 . I was fortunate to have some truely golden mentors to learn from and to build on .

I had a rifle rebarreled for 7×6.8 SPCII and needed to work up loads . Well there just aren't a lot of commercial 7mm bullets under 120 gr and moulds tend to start there and go up as well . 270 moulds are about as common as 25 yo virgins and they are really all 130s or a variation of . Poor planning on my part . So I chose what seemed to be a flexible powder and checked book data against some old Sierra 120 SP flat base 7mm bullets against the tested data for 120s in the 6.8 . Well that data all worked within the limits of my scales , Chrony and bench . So far good practice whether working up blind for random components or with a change of components . Verify data and work up . If the data agrees then expand to the unknowns with the knowns and be safe ........right ?

Not always . I had a design plan in mind for the rifle . Ms had a deer tag for a NV mule deer and the area was easy living and allowed for plenty of shots typically inside 150 yd .
I started working up a paper patched 27-130 flat point. No problem I had some limited data for 130s and suitable powder , primer , and brass for the test on hand . I had a 3.0 window and worked it in .3 gr steps . The data showed 2450 fps could be reached in a 16" AR carbine so a 21" bolt gun should be a piece of cake ........
That's great except .....
I worked the load up , getting velocities that were just a little slow at the start but with each step closed the gap just a little . 10 loads of 5 each and groups closing and alloy working well I was happy as a pig in mud . Now since I was well within that data I was only passively looking cases and primers and not really feeling the bolt lift , not that it was noticably heavy anyway . Load number 7 broke 2400 fps and shot 1,2" . That was smaller than the 1.75 of load 6 . So I went on and load #7 vented the primer and chronied the same as #6 on the first shot I fired a second because "I knew I was well inside of good data " . It also vented . The LRP pockets were now .25 instead .210 vented . At first glance I blamed the Win LRP primers and the Rem brass . I stopped there and went back to the bench , probably the only smart thing I did .
I weighed the remainder of the brass after I checked the scale for accuracy . The brass was all within a reasonable limit of tolerance . Trim lengths were all good , even on the blown cases , maybe even a little short after the chamber cast was done . In a final fit of head scratching I threw one of the wet wrapped , dried , and slicked up bullets .....
The normal average over is 1-3 gr over for almost all of my moulds notable exceptions are an NOE 225-55 @62 gr , but it came along well after this event , and Lee 452-255 that tip in at 265 gr . Now 10 gr isn't much on a 255 gr bullet that's less than 4% the 7 gr on the 55 is steep but since all 5 cavities throw within .1 gr and there is 62 gr data available it's not a big deal . Back to the bullet on the scale . Remember it was supposed a 130 gr bullet ? Well RCBS is rated on linotype metal and my as hard but more maluable metal was heavier but I would not have expected 142 gr from a 130 gr mould .

Lesson learned , new components or new sources require checking since that learning experience I've found lot to lot jacketed bullets vary by as much as a grain . I did find a box that was 5 gr heavier than another but it was a brand new box compared to a 30 yo box and there were jacket and core alloy changes and they may have run in the same dies , 180 Spitzer boattail the old bullets were 178-9 and the new were 183.1-2 30 cal .

Weigh an unknown bullet , weigh new lots , weigh changes in alloy for those that cast .
I suppose that this goes for every component .

Fortunately neither I nor the rifle was damaged beyond my pride . Fortunately the rifle was built for a much lighter cartridge than it's original however it's design was for a 48-50kpsi cartridge not a 55-58kpsi cartridge and it wasn't intended to shoot a steady diet proof loads which is what it was fed with that work up . Good news , it lived .

mattw
08-29-2018, 10:33 AM
Good story with good lessons. I started with 6mm/284 when it was a very young wildcat. As we all know, this round is a rocket with the lighter weight 6mm bullets. This was my long range prairie dog gun in those days. I worked up loads here in the dead of summer as I expected it to be hot out in SD over the first or second week of July. This is basically an F class gun, 30" barrel, full diameter of 1.25 inches and a tight chamber, 1.25 oz trigger and 8x32 scope. We made the trip out with it the first year and I must say in the mornings it was a great rifle, but by afternoon the bullets were disappearing about 40 feet out. The 20+ degree difference in temperature was jacking my load up so much that I decided not to shoot it past about 90F that first year. I did not blow or vent any primers, but I have a feeling it was not far off as the primers were extremely flat at the higher temps.

Lesson learned? You bet. Took loading gear the next year and worked up some new loads out there on the first day. We shot in 2 man teams, a spotter working the wind and confirming the kill and a shooter. It was so satisfying ranging out confirmed kills in the 865 yard range!

OverMax
08-29-2018, 11:52 AM
Enjoyed the write Rich. I think you missed your calling sir. All your learning stories should have been entered in a book/published for all to read.

Three44s
09-09-2018, 09:49 AM
It is always better when a learning lump does not come also with any real lumps ..... Ie. .... it is good you and your rifle are fine!

Three44s