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View Full Version : Precision load test for a friend.



nf1e
05-05-2017, 09:31
This is being done for a chronograph test only. Using like rifles and barrels.
After getting specific recipe from my friend along with desired bullet jump, it is time to select exact components to duplicate load. Powder,brass, primer and bullet.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0966_zpsj1wct9tl.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0966_zpsj1wct9tl.jpg.html)

Powder charge.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0967_zpspmexzn9e.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0967_zpspmexzn9e.jpg.html)

Seat bullets.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0969_zpsbmnbw8ol.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0969_zpsbmnbw8ol.jpg.html)

Set precision die to desired CBTO to allow recipe bullet jump.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0968_zpsuoj4v0e1.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0968_zpsuoj4v0e1.jpg.html)http://


Mission accomplished. Now wait for the dang rain to stop so I can go outside an do the chrono tests.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0972_zpsunnjgyud.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0972_zpsunnjgyud.jpg.html)

Semper Fi
Art

Sunray
05-05-2017, 10:20
To duplicate the load(kind of a waste of time since every rifle shoots the same ammo differently.) you need to use the exact same components and the rifle that load was worked up for.
You can forget the off-the-lands stuff altogether as it's a different OAL for every rifle.
It's entirely unnecessary anyway. The whole off-the-lands thing is a load tweaking technique done, if you feel like it, after you've worked up the load. Finding the preferred distance off the lands in a 100% trial and error thing as well. There's no formula or standard distance.

nf1e
05-05-2017, 10:38
To duplicate the load(kind of a waste of time since every rifle shoots the same ammo differently.) you need to use the exact same components and the rifle that load was worked up for.
You can forget the off-the-lands stuff altogether as it's a different OAL for every rifle.
It's entirely unnecessary anyway. The whole off-the-lands thing is a load tweaking technique done, if you feel like it, after you've worked up the load. Finding the preferred distance off the lands in a 100% trial and error thing as well. There's no formula or standard distance.
Thank you very much for your opinion Sir.
Actually this is for chronograph test only. The jump my friend was using in his rifle is duplicated using my rifles CBTO and set for a .0012 jump. After 50 plus years of messing with this stuff, we have it pretty well nailed. Same barrels and same components down to brass weight,primers, powder and bullets. Pretty simple. My friend is in Texas and I am in CT. There is no reason this will not work perfectly, it has many times before.
Realizing that the CBTO is different for every rifle and depends on exactly the bullet being used it is important to know all measurements. Again, thanks. Most rifles with show accuracy nodes about every .0010 from contact to way past .0100 in my experience. Then the tweaking can get interesting.

nf1e
05-06-2017, 03:11
Got out and did the test for my friend today. With my LRB M25 at 150 yds we made a decent 5 rnd group.

http://i1180.photobucket.com/albums/x413/nf1e/IMG_0974_zpsymsnezmv.jpg (http://s1180.photobucket.com/user/nf1e/media/IMG_0974_zpsymsnezmv.jpg.html)

Semper Fi
Art

Litt'le Lee
05-06-2017, 03:34
methinks you need to remeasure that !!!--that top 2 look more like 7/8"

nf1e
05-06-2017, 04:01
methinks you need to remeasure that !!!--that top 2 look more like 7/8"

How about an average of about .5 at 150, that ain't too shabby for and M-14 type rifle.

nf1e
05-06-2017, 04:39
This is the rifle I used for that. Not your standard M-14.

http://i1180.photobucket.com/albums/x413/nf1e/March272012accuracyweapons007.jpg (http://s1180.photobucket.com/user/nf1e/media/March272012accuracyweapons007.jpg.html)