|
Post by bigbrowndog on Aug 5, 2019 15:32:05 GMT -5
i know a proper crimp is necessary for good combustion and consistency with loads. I fired a few new loads the other day and the load should have given me a significant increase over my current load. The crimp was a stout crimp, and one I’ve used on my other loads but the increase in velocity was only 40fps, and the powder charge was a 3 grain increase. The current load is 33gr. with a 430gr bullet and velocity is 1170fps, the 36gr load is going 1210fps. Load data shows it should be doing 1350-1360fps, I’m wondering if a stouter crimp would help??? One of the issues in dealing with this bullet is that it is a jacketed one and pressing the crimp harder tends to simply flatten it against the bullet sides, it appears to actually deform the bullet sides a bit, so I am curious if some of you guys using jacketed bullets for the heavy recoilers are having similar issues. Mine is a 500Max, and I’m using both Woodleigh and Hawk bullets, 430gr and 450gr.
Trapr
|
|
|
Post by magnumwheelman on Aug 5, 2019 15:49:45 GMT -5
Unless I missed it, I did not see a powder listed... in my experience, it depends on the powder... some need a heavy crimp, & some perform just as well with a lighter crimp
|
|
|
Post by bigbrowndog on Aug 5, 2019 15:57:32 GMT -5
Something else I missed was primer type,......powder is H 4227, primer used in load data is Fed210, I’m using CCI 350, magnum pistol vs large rifle. So maybe a couple of things going on here.
Trapr
|
|
|
Post by Encore64 on Aug 5, 2019 16:02:56 GMT -5
Well, it's more neck tension than crimp. Crimp may play a small part, but neck tension is paramount.
|
|
|
Post by leftysixgun on Aug 5, 2019 17:36:12 GMT -5
In my recent experience with my 480, primers make a huge difference! So what powder and primer are you using?
|
|
|
Post by bigbrowndog on Aug 5, 2019 17:50:11 GMT -5
Encore, the interesting thing is I’ve had good results with the 33gr load and reasonable velocity differences, within 30-60 FPS of expected velocity. Not so with the same bullet and crimp tension and I assume the same neck tension considering it’s the same dies, bullets and crimp.
Lefty, I reposted the powder and primer data.
Trapr
|
|
|
Post by Encore64 on Aug 5, 2019 18:01:16 GMT -5
I was having the same issue. I added a Hornady Taper Crimp die. Now, I taper crimp AFTER I roll crimp on 475 Linebaugh, 480 Ruger and 454 Casull.
It works for me...
|
|
|
Post by bigbrowndog on Aug 5, 2019 18:05:22 GMT -5
That’s a thought, I may try it.
Trapr
|
|
|
Post by 45MAN on Aug 5, 2019 19:10:38 GMT -5
DOUBLE CRIMPING WITH DIFFERENT CRIMP DIES IS AN AREA THAT MAY NEED MORE INVESTIGATION. ON SOME LOAD OR LOADS, TRADMARK DOES A PARTIAL ROLL CRIMP AND THEN A LEE F/C DIE CRIMP. I WAS LOADING SOME 480's ON A DILLON AND THE LEE F/C DIE WOULD NOT REACH SO I USED A REDDING PROFILE CRIMP DIE AND THEN IN A SINGLE STAGE PRESS FOLLOWED UP WITH THE LEE F/C DIE. IT WORKS VERY WELL. I HAVEN'T COMPARED JUST PROFILE CRIMPED LOADS TO THE 2 CRIMP LOADS BECAUSE I FEEL REAL GOOD ABOUT THE 2 CRIMP LOADS.
I WAS RECENTLY READING AN ARTICLE BY THE GRIZZLY CARTRIDGE GUY, AND HE SAID SOMETHING TO THE EFFECT THAT SHALLOW CRIMP GROVES ON JACKETED BULLETS CAN CAUSE CRIMPING PROBLEMS. I SUSPECT THAT GRIZZLY AND BUFFALO BORE USE CUSTOM MADE CRIMPING DIES AND STAY AWAY FROM SHALLOW CRIMP GROVE BULLETS.
|
|
|
Post by bigbrowndog on Aug 5, 2019 19:18:03 GMT -5
The taper crimp followed by a roll crimp sounds like it hold some promise, I’ll surf midway and see about a taper crimp die for 500 Linebaugh. It sounds like a bit of a pain, but considering that once load development is finished, 50 rounds should last a year for practice and hunting, really isn’t too bad.
Trapr
|
|
|
Post by Encore64 on Aug 5, 2019 19:21:13 GMT -5
The taper crimp followed by a roll crimp sounds like it hold some promise, I’ll surf midway and see about a taper crimp die for 500 Linebaugh. It sounds like a bit of a pain, but considering that once load development is finished, 50 rounds should last a year for practice and hunting, really isn’t too bad. Trapr Tried that, didn't work. Roll crimp followed by taper crimp.
|
|
|
Post by bigbrowndog on Aug 5, 2019 19:48:58 GMT -5
Ok, so the order made a difference, good to know.
Trapr
|
|
|
Post by leftysixgun on Aug 5, 2019 20:17:36 GMT -5
I think you need to switch the large rifle primer like the data says. Do you have a strong hammer spring? I have actually seen a small velocity gain when going back to atleast factory (from a lighter weight spring) weight spring. Just a couple thoughts out loud.
|
|
|
Post by bigbrowndog on Aug 5, 2019 21:39:15 GMT -5
Lefty I’m going to try the primer switch first as I have them on hand, and the die will take some time to acquire. Some 500Max data I’ve got uses CCI LPM primers and other data lists Win LR and Fed LR, so I’ll do that first.
Trapr
|
|
|
Post by leftysixgun on Aug 6, 2019 5:39:22 GMT -5
Keep shooting over a chronograph but also keep track (notes) of your extreme spreads and standard deviations.
|
|