I am a little surprised, I didn't think there would be that much difference. I will reshoot the following with Federal 209A primers and 10 shot strings, mostly because I really don't trust Cheddite primers to be the best primer for the job. 10 shots strings are more reliable. However, the tendency that a crimp finisher makes a load more consistent is obvious, at least in these two loads.
All powder and shot drops were weighed. Reloaded on a MEC Sizemaster.
On 2/27/2025, Sunny 46 degrees F, RH 63%, SW wind @12 MPH. Reference load with an assessment value of 1,165 FPS, averaged 1,173 FPS. 16 ga. Rem 1100, 28" barrel with .000" choke. 3 warming shots. Chronograph, ProChrono Plus, with baffle at 24" in front of start screen, muzzle set at 30" in front of start screen. 5 shot strings. All ammo, including reference, was kept at 55 degrees until shot.
Load #1 (directly from the Gualandi data)
Winchester/Cheddite 2 3/4" hull
Cheddite CX2000 primer
20.8 Grains Vihtavuori N320 powder
Gualandi BRG 16/21 wad (SG16)
1 oz. lead shot
Without OMV Crimp finisher
Average - 1,190 FPS
Hi - 1,204 FPS
Lo - 1,170 FPS
ES - 34 FPS
SD - 14 FPS
With OMV Crimp Finisher
Average - 1,212 FPS
Hi - 1,222 FPS
Lo - 1,200 FPS
ES - 22 FPS
SD - 9 FPS
Load #2 (modified from IMR data, primer and wad)
Remington 16 ga. 2 3/4" hull (RGL)
Cheddite CX2000 primer
21.0 Grains IMR SR7625
CB0100-16
1 oz. lead shot
Without OMV Crimp finisher
Average - 1,210 FPS
Hi - 1,244 FPS
Lo - 1,189 FPS
ES - 55 FPS
SD - 21 FPS
With OMV Crimp Finisher
Average - 1,211 FPS
Hi - 1,225 FPS
Lo - 1,200 FPS
ES - 25 FPS
SD - 9 FPS
The slight increase of average velocity in Load #1, is probably due to the OMV putting a slightly deeper crimp on the hull. With Load #2, the depth of crimp did not change.
All powder and shot drops were weighed. Reloaded on a MEC Sizemaster.
On 2/27/2025, Sunny 46 degrees F, RH 63%, SW wind @12 MPH. Reference load with an assessment value of 1,165 FPS, averaged 1,173 FPS. 16 ga. Rem 1100, 28" barrel with .000" choke. 3 warming shots. Chronograph, ProChrono Plus, with baffle at 24" in front of start screen, muzzle set at 30" in front of start screen. 5 shot strings. All ammo, including reference, was kept at 55 degrees until shot.
Load #1 (directly from the Gualandi data)
Winchester/Cheddite 2 3/4" hull
Cheddite CX2000 primer
20.8 Grains Vihtavuori N320 powder
Gualandi BRG 16/21 wad (SG16)
1 oz. lead shot
Without OMV Crimp finisher
Average - 1,190 FPS
Hi - 1,204 FPS
Lo - 1,170 FPS
ES - 34 FPS
SD - 14 FPS
With OMV Crimp Finisher
Average - 1,212 FPS
Hi - 1,222 FPS
Lo - 1,200 FPS
ES - 22 FPS
SD - 9 FPS
Load #2 (modified from IMR data, primer and wad)
Remington 16 ga. 2 3/4" hull (RGL)
Cheddite CX2000 primer
21.0 Grains IMR SR7625
CB0100-16
1 oz. lead shot
Without OMV Crimp finisher
Average - 1,210 FPS
Hi - 1,244 FPS
Lo - 1,189 FPS
ES - 55 FPS
SD - 21 FPS
With OMV Crimp Finisher
Average - 1,211 FPS
Hi - 1,225 FPS
Lo - 1,200 FPS
ES - 25 FPS
SD - 9 FPS
The slight increase of average velocity in Load #1, is probably due to the OMV putting a slightly deeper crimp on the hull. With Load #2, the depth of crimp did not change.