Re: Data for ALL Cals Ackley Imp
Jan 2000 I buy Keunhausen's scatter brained book on Mausers.
Feb 2000 I buy a VZ24 surplus rifle from BIG5 for $70.
Mar 2002 I buy a Lothar Walther .257 light varmint barrel $145
I get .257 Roberts Ackley Improved reamer from Dave Manson.
I build an action wrench.
I build a barrel vise.
I make an action truing mandrel.
I make a lug truing cartridge.
I make an inner C ring lapping tool.
I do a trigger job on the military trigger to control take up, force, and overtravel. Pull is down to 1 pound.
The bolt is bent with an Acetylene torch and sledge hammer.
I buy a Wheeler Eng drill and tap fixture and drill and tap.
Weaver #45 and #46 steel mounts are glass bedded to the receiver.
The barrel is dialed in on both ends of the lathe to within .0001".
Threads and chamber are cut.
The chamber measures still concentric on the lathe to with in .0010".
Stock is sporterized and glass bedded to the barrelled action.
A 40X Leupold scope is installed.
Barrel is cleaned and burnished with moly bore cream.
Winchester Brass is fire formed with 10 gr pistol powder and back filled with Cream of Wheat.
Case mouths are chamfered inside and out.
Forster dies are used on a Rockchucker.
Bullets are 75 gr Vmax moly coated for me by Russ Hayden.
Powder is surplus bulk military pull down IMR4895 that act more like H322.
Bullets are seated long to jam into the lands.
Late 2002:
1) 48.3 gr. gives 3757 fps and the extractor groove grows .0005"
2) 47.2 gr. gives 3736 fps and no extractor groove growth
3) 45 gr. gives 3674, 3621, 3630, 3614, and 3630 fps
A) All 5 shot 100m groups over last 6 years with 75 and 72 gr bullets average .87".
Can consistently shoot less that .5" when there is no wind at all.
B) With Hornady 100 gr soft point blem bullets, and 8.5x25x50 Mark IV scope, groups are less than 1" with 42 gr surplus bulk IMR4895 3220 fps