Discussion in 'Big Stuff -- 6.5mm, 7mm, 30 Cal' started by Rockfish Dave, Aug 5, 2013.
Thanks for all of the post. Enjoyed the project and read.
Just took the 308WIN barrel off and put the 6.5slr-s improved barrel on, so weather permitting I will have the load testing through 43grs completed tomorrow.
One note: the jump to lands is .052 for 41 - 42grs. For the remainder it is .002. An oversight that I didn't feel like correcting. I expect the groups to open up, and since I documented 41grs previously it should be a good indication of the impact of jump to the lands for the Lapua Scenars.
Did I understand that you were jumping the lands .052", but now it will be .002", or now it will be .054".
I have the wildcatting bug also! Could you please post your max velocity with 140gr bullets with your 6.5SLR Improved case?? I would like to see a set of targets as well shooting an OCW test up until you see extractor marks with H4350 and 140gr bullets (hybrids.) What was your case capacity improvement after reducing the taper???
This next batch was jumped .052" to the lands on the loads between 41 and 42 grains.
When I measured for the dummy round, something was not correct. When I checked my notes on COAL I saw that I had been loading .050 shorter than my original loads. I chambered the old dummy round and it was just kissing the lands. So I changed the seating depth and verified by chambering the loaded round, it was just kissing the lands.
So for the rounds over with charges over 42 grains it will be at the lands just like before.
I'm going to include rounds uo to 44 grains, but those are hydroformed cases.
All brass has been prepped and annealed before firing.
Working on it.
I'll try to keep to the format like before. I barely have time to load and shoot, so deep diving into all the measurements (neck thickness, h2o capacity, etc. just aren't going to get done).
The goal is to share just in case anyone was interested in something a little different, without having to start from scratch.
I'm just interested in the OCW or Ladder accuracy node with H4350 and 140gr hybrids.. Also, the velocity within that node.. I'd say if you can get a node around 2,950fps with case life you'll have succeeded with what I would like.. I can get 2,790fps with 40.1gr H4350 and have a node around 41.7gr with my 6.5x47, so if you can get lucky and have a node at 2,950fps that would be great in my book! What's your freebore length?? Also, I would love for you to work an H4350, 140gr hybrid load up with Lapua Palma cases! Have you ever tried Palma cases with it before??
I don't have any Hybrids, so not anytime soon.
The palma cases I am interested in. If this gets me the velocity I want, I'll probably spring for the palma cases some time in the future since the benefit's of small primer pockets (lower ES and longer brass life) will warrant the extra effort (stepping down to 7-06, and neck turning).
The ladder test will have to wait until I know what my working load range is, and I weight sort my brass. I probably will not bother to post the results though...
As it stands I'm just going to finish posting these results and get back to shooting. Once I'm finished it should give you an idea if you (or anyone else) wants to go down this road.
Just got back from the range. Shot the 42-44 grain rounds (was very tight on time). The first couple of series were fire forming rounds and still had the wonky velocity spread. The hydroformed rounds had a tighter *edit* meant ES not sd (single digit or low teens).
The 44gr rounds had a single digit sd, and shot great. No issues with extraction, or signs of pressure. These were the hydro formed cases. *edit* just looked at the pictures of the fired rounds posted earlier in the thread and the primers look exactly like the lighter load one's, except the firing pin strikes are dead center on the hydroformed cases ;-).
The velocity was just over 2900fps. I am very happy with the results, especially since I can run a little more powder if I wanted to.
I'll post the magnito speed results when I have a chance.
To sum up how I feel about my little experiment; I will be keeping it! Once this barrel burns out I'll get another!
When " I believe, therefore, it must" turns into " It sure as hell does" !!! Ain't it great?! Congratulations Rockfish Dave.
I may get one of those my ownself
Thanks, I'm kind of relieved.
I did a little less taper than the Ackley recommended of .0074 per inch (if my memory serves, as I read it in one of his books and wrote it down in my notes which are not handy at the moment).
As a "S.W.A.G.", I was thinking that since the surface area is less than a 'o6 caliber case, what I assumed were what he was referring to and since the Magnums have a minimum taper of .01 per inch. It appears to be working just fine.
One disclosure is I did polish the chamber with flitz using a .45 bore mop with a high speed drill when I got it back from the smith.
I'll continue doing load development and updating the thread as I get there. It will most likely just be load specifics and MagnetoSpeed results.
I definitely am curious where the upper limit is now given the primers were just barely touching the bolt face, but not flattened. Just a guess, but I probably have another .5 grain to as much as 1 grain to go. Hunting season starts Saturday here so unless I fill my tags early in the season this will probably be as far as I get this year.
Knowing 2,900fps can be had with the smaller 6.5x47 and reports of 3,000fps with an improved version of it and 140gr bullets, I feel your experimenting needs to be done with Lapua Palma brass for sure to see the true potential of your cartridge...
Do you happen to know what your Case capacity is in water weight?
I tell you what; Since you are so persistent I will be happy to accommodate your request on testing with the Lapua Palma cases and the Berger Hybrids.
Just pick up a box of brass and bullets, and I'll supply the powder, primers and labor. I will even do the ladder test with the remaining ten rounds after load development.
Ha! Love it.
Thank you sir, I'm here all week and two shows on Sat.
Russel and John, I'll get the H2o measurements for ya as soon as I can. Filled to the top. the neck/shoulder junction, or at the shoulder/body junction?
Normally right to the top. You will get a dome of water protruding up or concave if you dont use a tid bit of Dish Soap or Rubing alcohol ( don't use good Burbon for this please) to break the surface tension. the corner of a paper towel can draw out any extra until it is level with the case mouth.
No hurry just wondering what you got. I wanted to plug it into quick load. Very best of luck to you on this seasons hunt.
Figured it was for quickload. Since I don't have/use it I haven't done it. I'll see if I can find an non-hydroformed 6.5 SLR-S case for comparison, it might be fun to see what the pre, and post capacity is. What do you think? Once I load it up I can just fire form it suppressed.
Also the barrel is now Salt bath Nitrided, so it takes a little more powder to get the same velocity normally. I can't say if that is the case for this barrel since I just put it back on. Not sure if quick load accounts for that.
As a favor can you see what H4830 and H1000 look like just for kicks?
Thanks for the good wishes on hunting. Opening day was a bust, but I have to admit I spent most of the day working on my cabin project... normally I reward myself with some shooting after working on the cabin, but with hunting season starting today there was no carrot at the end.
Anymore info on this?
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