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300PRC

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https://forums.accuratereloading.com/eve/forums/a/tpc/f/2511043/m/1631030182

05 April 2025, 16:14
M 98
300PRC
i recently got hold of various makes of 300 PRC brass ADG etc etc and necked them up to .375 (RUGER)
All went well, brass was fire form and turned out all good
Just wondering is it stretching the friendship with the 300 PRC brass if i was to neck it up to .416
i basically want better quality brass for the 375 and 416 Ruger then the Hornady brass
Any comments would be appreciated
Daniel
13 April 2025, 21:06
Live Oak
I have a rod anvil mike, thought I would measure the neck thickness as I necked up. I have Lapua 300PRC brass, going to 375 Ruger with Hornady die was easy with sizing wax. The Hornady expander button is long and tapered. The expander button on my Redding 416 Ruger die is short and blunt, it did not work! It started off center and crushed the neck. Maybe going up to 40 cal with a tapered button then to 416 with a tapered button might work. Lapua brass measured 15.5 thousandths, to 375 reduced it to 14.5.
Not much help, I tried!
13 April 2025, 21:43
buffybr
I've successfully expanded .300 RUM and 7mm RUM up to .375 RUM with one stroke with a little Imperial wax in the case mouth, and with a long taper expanding plug that I made. Don't anneal before expanding or the case shoulders may crush.



NRA Endowment Life Member
16 April 2025, 16:25
M 98
WHEN I NECKED UP THE ADG 300 PRC BRASS TO 375 RUGER. I NECKED UP IN SMALL INCREMENTS 8MM EXPANDER , 338 , 35 9.3 AND THEN WITH A 375 EXPANDER...FIRE FORMED WITH A 300 GN CAST BULLET AND LOST NO CASES
MIGHT GIVE IT A GO AND TRY TO GO UP FROM 375 TO 416 AND SEE HOW IT TURNS OUT
DANIEL
22 April 2025, 13:20
M 98
Just an update, got a 300 PRC case which i necked up to 375 RUGER with no issues and then fire formed it.I didnt have any expander buttons that i could take two or 3 steps to get to .416, from .375 so just used the tapered expander button on the redding .416 die and bingo....416 case from a 300 PRC (ADG BRASS) in one go.
Fire formed it with a cast bullet load, and will now give it a good clean, and measure the thickness of the neck wall...will report back!!
22 April 2025, 17:48
jeffeosso
general comment - imperial sizing wax is amazing, and if you think you have just the right amount, halve that!!


opinions vary band of bubbas and STC hunting Club

Information on Ammoguide about
the416AR, 458AR, 470AR, 500AR
What is an AR round? Case Drawings 416-458-470AR and 500AR.
476AR,
http://www.weaponsmith.com
27 April 2025, 18:04
matt salm
When fire forming the 375, I assume you jammed a bullet hard to the lands? A friend was doing the same and had one that he seated to mag length working on feeding…that one separated the case head as he forgot about that short one.


Shoot straight, shoot often.
Matt
01 May 2025, 13:39
M 98
using cast bullets that were powder coated , had the same effect as seating them into the lands , as the cast proj are pretty tight with the coating
01 May 2025, 18:48
ted thorn
quote:
Originally posted by M 98:
using cast bullets that were powder coated , had the same effect as seating them into the lands , as the cast proj are pretty tight with the coating


Were these not sized after powder coated?


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03 May 2025, 18:05
M 98
the cast bullets are double diam...hard to size the nose/bore riding part of the projectile