17 Mach IV

kciH · #1 01-28-2003, 09:29 PM

I just recieved a new Contender Carbine barrel from Bullberry Barrels in 17 Mach IV. If anyone has any tips on brass forming or load data it would be greatly appreciated. I have some data from the Ackley books and another source, but modern powders would be nice. I'm looking forward to shooting this, as the last barrel from this company was extremeley accurate for a TC. The first 10 shots of my 6.5 Bullberry (6.5-30) went into less than an inch, with case forming loads. I've since got some varmint and hunting loads that are approaching 1/2 moa. It'll do 3/4 moa all day long if I do my part. Any info would be greatly appreciated.

kdub · #2 01-29-2003, 01:09 PM

The Bullberry's are nice barrels.

I had one in the 6.5-30, also for the T/C carbine. Presently have a .375 Winchester bull barrel from them that is a great shooter, too.

alyeska338 · #3 01-29-2003, 03:49 PM

kciH,
I have an article written by Steve Timm on the Mach IV and it relates: ".221 Fireball cases are necked to approximately .20 caliber by running them through the Redding .17 Mach IV Form Die No. One. Next, the cases are inserted into a .17 Mach IV trim die. The trim die reduces the neck to .178 inside diameter. Then the brass is sized in a .17 Mach IV full length sizing die. To ensure proper headspacing the sizing die should be adjusted so the rifle bolt will barely close over a processed case." He does go on to state that he trims and squares the necks and turns the case necks. He also says that "forming from a 221 case involves a neck reduction of about 23 percent - that would be like necking a .30 caliber case to .23 caliber."

A few loads mentioned are (25 grain Hornady Hollowpoint):
14.2 grains IMR-4227 3,565 fps
16.5 grains IME-4198 3,590 fps
18.5 grains H-322 3,693 fps
19.0 grains " 3,762 fps
19.5 grains " 3,827 fps
19.0 grains H-335 3,642 fps
19.5 grains " 3,755 fps
20.0 grains " 3,884 fps
20.0 grains BL-C(2) 3,610 fps
20.0 grains W-748 3,510 fps
Loads fired from a Kimber Model 84, 22-inch sporter barrel, 10 inch twist Rem 6 1/2 Primers. All powder charges should be reduced by 10 percent for starting loads. Oehler 33 chrony.

kciH · #4 01-29-2003, 07:48 PM

Alyeska338,

Thanks for the info. The case forming is about what I was expecting. The folks at Bullberry make it a little easier in that they sell a universal die that necks down any 22 case to 17 in one pass so that the case forming dies are not needed. I'm hoping it works as easily as they say it does.

alyeska338 · #5 01-30-2003, 04:21 PM

kciH,
If you start having problems with ruined cases, Timm wrote that he had no rejects. Just something to keep in mind, it might be less stress on the case to do the sizing through a couple of operations rather than trying squeeze everything down at once.

Let us know how the Bulberry works.

zooly · #6 07-25-2003, 07:16 PM

Does anyone out there have form and trim dies for the .17 Mach IV, that would be willing to run 200 or so 221 cases for a small fee?