6mm bullets are available in a large array of types and weights. 60, 70, 75, 80, 85, 90, 100 and 105 grain sizes, and hollow point, spitzer, semi-pointed and round-nosed, in flat and boat-tail design, are offered. All point and base types aren’t available in every weight, of course.
Aside from the new Remington Power-Lokt bullets, there are no factory 6mm match grade bullets on sale. Gardiner of Rockford, Ill., now specializes in 6mm bullets, match and hunting types, and Col. Hollidge is well known for his match bullets, 6mm as well as 224, etc.
My 40-XB was factory tested with Crawford Hollidge (Marstons Mills, Mass.) bullets, so a supply of these was ordered. These are soft swaged, hollow pointed and run about 70 grains. Later on some heavier Hollidge bullets were also purchased.
My first groups were fired, after sighting in, with factory 100-grain ammunition. It would be a gross understatement to say that accuracy left something to be desired, for the last three 5-shot groups averaged about 1½”.
However, as it was about 15 months since I had done any serious rifle shooting I laid part of the blame on being out of practice. Such didn’t prove to be the whole case though, because after I had become used to the rifle and shooting from a bench again, groups with the other box of factory loads didn’t improve much, going about 13⁄8″ average for four groups.
After all cases had been fire-formed I began loading and shooting in earnest.
Without a doubt the best shooting load was the one used at the factory for testing accuracy, i.e., 40.5 grains 4064 and the 70-gr. Hollidge soft swaged bullets. This load averaged .380″ for a series of groups.
|Here is a table of my results, the group sizes being the average of about 5–6 strings of 5 shots:|
Bullet Powder Group
Gardiner 70-HP 40.5/4064 .625″
Hollidge 70-HP 40.5/4064 .380″
Sierra 60-SP 41.0/4064 .625″
Sierra 75-HP 39.0/4895H .625″
Speer 90-SP 35.0/3031 .800″
Speer 105-RN 35.0/4320 .750″
It became apparent that the lighter weight bullets were the shooters, because for the most part anything over 75 grains didn’t perform well. Also that 4064, combined with light bullets, gave the best accuracy.
I like boat-tail bullets, but the Sierra 85-gr. BT just won’t shoot in this 40-XB, groups running around 1″-1¼”.
Remington has two new 6mm bullets on the market — on the market if you can find them, that is! One is a hunting type, the other target style, both 80 grains.
So far the only one that I have had a chance to shoot has been the hunting bullet. This is rather odd looking in that it could, in all truthfulness, be called a full metal-jacketed hollow point, with a dimpled bottom! How does that grab you?
The nose of the jacket is folded over and in and, looking closely, you’ll see 5 cuts in the nose for quick expansion. Do they shoot? You’re darned right they do. The first load, using 40 grains of 4320, gave a 1⁄2″ group. Going up and down (very little up, though) in ½-gr. jumps neither hurt nor helped group diameter. With its small diameter hollow point, this should be a flat-shooting bullet.
The Norma 75-gr. HP bullet shoots well too, though not quite as good as the Remington. 40 grains of Norma’s No. 203 gave an average of about 3⁄4″, and I finally settled on the Norma recommendation of 42.3 grains of 203, with groups wavering between 5⁄8″ and 11⁄16″.
Of interest to me was the velocity consistency of the various loads. Some were markedly better than others. Lowest variation came with the 80-gr. Remington bullet ahead of 40 grains of 4320 — a mere 11 fs. 35 grains of 3031 with the 80-gr. Speer was almost as good, 19 fs. Least consistent was the load using the lightweight 60-gr. Sierra — 89 fs. Remington’s factory load varied only 30 fs, good results with machine-loaded ammo.