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I've got a 527 that I bedded into a Boyd's Heritage stock with a cheek piece suited for my left handedness. The rifle shoots a couple factory loads into sub MOA groups. I spent a couple range sessions getting pretty terrible results with H4895 and 120 Nosler BT's. Nice velocities but no amount of fiddling with seating depth or powder charge could get me into a happy place. I tried some rounds loaded for my 527 MTR with 108 Scenars and verified that the scope or anything else isn't to blame.
My goal is to have a bullet suitable for animals, not that I'm a hunter, but this is a hunting rifle. I might need to take out a pesky coyote where I live.
I abandoned the 120 BT's and had some 95 VMAX kicking around that would fit the bill. I checked Quick Load and saw that H322 favored well with decent case filling and 100% burnt in the barrel. I refuse to use the standard loved ball powders like CFE 223 and H335 due to the temperature swings we get here. It can be -40 to plus 90 something so I prefer the Hodgdon Extreme powders.
Using a Hornady seating gauge, I determined that 95 VMAX are touching the lands at an OAL of 2.25" therefore I started seating with about .015" jump.
Since I have two Grendels, and sadly the chambers are quite different, I run one type of brass in each so it makes it easy to differentiate. The MTR gets Lapua and the American get the Federal.
I started off with CCI 450's and did some with 7-1/2's later on.
So this is what I got, all charges with H322 and 450's, three shot group unless stated....
28gr..... .705" No velocity (Labradar set for mid range from yesterdays airgun testing)
28.5..... .655" 2792 SD 6.8
29.0..... .565" 2830 SD 2.5!!
29.5..... 1.4" 2887 SD 10
30.0..... .735" 2940 SD 24
Well that was more promising than the 120 BT's!!
Next up, 5 shot groups with some of the favorites above.
29.0..... .885" 2833 SD 6.9 (CCI 450)
29.0..... 1.4" 2847 SD 8.9 (Rem 7.5)
30.0..... 1.3" 2962 SD 11.4 (Rem 7.5)
Clearly adding the 7.5's to the mix was a bad combo.
I ran out of light and still wanted to test the 30gr charge with 450's and 5 shots. I'm going to clean the bore as well and start fresh as I think I'm around 80 rounds. I ran the brass through the AMP annealing machine and have it sized and drying after a trip through the SS pin tumbler.
My goal is to have a bullet suitable for animals, not that I'm a hunter, but this is a hunting rifle. I might need to take out a pesky coyote where I live.
I abandoned the 120 BT's and had some 95 VMAX kicking around that would fit the bill. I checked Quick Load and saw that H322 favored well with decent case filling and 100% burnt in the barrel. I refuse to use the standard loved ball powders like CFE 223 and H335 due to the temperature swings we get here. It can be -40 to plus 90 something so I prefer the Hodgdon Extreme powders.
Using a Hornady seating gauge, I determined that 95 VMAX are touching the lands at an OAL of 2.25" therefore I started seating with about .015" jump.
Since I have two Grendels, and sadly the chambers are quite different, I run one type of brass in each so it makes it easy to differentiate. The MTR gets Lapua and the American get the Federal.
I started off with CCI 450's and did some with 7-1/2's later on.
So this is what I got, all charges with H322 and 450's, three shot group unless stated....
28gr..... .705" No velocity (Labradar set for mid range from yesterdays airgun testing)
28.5..... .655" 2792 SD 6.8
29.0..... .565" 2830 SD 2.5!!
29.5..... 1.4" 2887 SD 10
30.0..... .735" 2940 SD 24
Well that was more promising than the 120 BT's!!
Next up, 5 shot groups with some of the favorites above.
29.0..... .885" 2833 SD 6.9 (CCI 450)
29.0..... 1.4" 2847 SD 8.9 (Rem 7.5)
30.0..... 1.3" 2962 SD 11.4 (Rem 7.5)
Clearly adding the 7.5's to the mix was a bad combo.
I ran out of light and still wanted to test the 30gr charge with 450's and 5 shots. I'm going to clean the bore as well and start fresh as I think I'm around 80 rounds. I ran the brass through the AMP annealing machine and have it sized and drying after a trip through the SS pin tumbler.
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