Setup: Nice day at the range. 83 F, 77% humidity. 4-6 MPH tailwinds/switching.
CZ 457 with RWS Rifle Match (RWS RM), Lapua Center-X (CX), Lapua Biathlon-Xtrema (BX).
Prone on a shooting mat with a bipod and rear bag.
6x5 shot at 50 yards, then 2 group of 5 at 100 yards and 8 shot group at 200 yards (10 shots but 2 were to verify getting on paper and or adjusting turrets to hit center).
Shooting sequence: RWS RM 6x5 @ 50, CX 6x5 @ 50, BX 6x5 @ 50, RWS RM 2x5 @ 100, CX 2x5 @ 100, BX 2x5 @100, RWS RM 10 shots @ 200, CX 10 shots @ 200, BX 10 shots @ 200. No foulers shot, 2 200 yard shots used to either get on paper or get to center of target.
Results:
50 yards
RWS RM avg = .676, best = .424, zero @ 50
CX avg = .415, best = .301, zero @ 50
BX avg = .657, best = .533, -.2 mil @ 50
100 yards
RWS RM avg = 1.102, best 1.055, 1.8 mil @ 100
CX avg = 1.076, best = 1.061, 1.9 mil @ 100
BX avg = 1.067, best = .861, 1.7 mil @ 100
200 yards
RWS RM 8 shot group = 4.198, 7.0 mil @ 200
CX 8 shot group = 2.467, 6.9 mil @ 200
BX 8 shot group = 2.785, 6.7 mil @ 200
Discussion:
1. As many have previously pointed out, Center X really shoots well near and at distance
2. Biathlon Xtrema had rather poor 50 yard results, but really shined at 100 yards and beyond. Likely shooter error, but more testing with this ammo is warranted
3. Biathlon Xtrema was hotter than the other 2 ammo. It only required 6.7 mil elevation at 200 compared to the others that were around 7.0 mil. I though i heard a few cracking the sound barrier. I wonder if this could have contributed to the scattered pattern.
4. RWS RM probably deserves another shot as I was fiddling with the bipod height and getting settled into a natural point of aim (NPOA) midway through the 6x5. My method of establishing NPOA was to have a gentle grip on the rear bag and rear stock with my shooting hand on the ground beneath the trigger. Then I relaxed fully and exhaled. If the crosshairs were not on the target, I would shimmy to get the crosshairs to line up on the target, then check position again as stated previously. Once the crosshairs were fully stable I would gently grab the stock with my firing hand and pull directly backwards while not disturbing the sight alignment/picture.
5. I was surprised by how well CX shot out to 200. I wish I had more time and ammo in hand to test
6. First 1 or 2 shots were off when changing ammo, but this rifle didn’t seem to mind switching between RWS FM and CX much. Both had the greasy lube where the BX had more of the traditional wax, but the BX groups did not improve through the 6x5 progression so I don’t think fouling played as much of a role during my session today
I’d welcome your constructive criticism and comments so I can improve as a marksman and hopefully help others to get the most out of the CZ 457.
YMMV and happy shooting.
