01-11-2022, 05:16 PM
A few months back I purchased a Whidden Gunworks Shoulder Bump Gauge .350 which is aluminum.
Last week I purchased a Sinclair Shoulder Bump Gage 30A which is steel, I prefer steel over aluminum for gages just my preference.
My question is why do I get two different readings, I thought the target for a bump gage was the .350" diameter on the shoulder.
When I measure a new Lapua case with the Whidden Gunworks Shoulder Bump Gauge .350 I get a reading of 1.190" to base
and with the Sinclair Shoulder Bump Gage 30A I get 1.127". That's .063" difference between the gages and looking at the
SAMMI 6.5 Grendel drawing it shows the shoulder length of 1.220 -7.
What am I missing here?
Last week I purchased a Sinclair Shoulder Bump Gage 30A which is steel, I prefer steel over aluminum for gages just my preference.
My question is why do I get two different readings, I thought the target for a bump gage was the .350" diameter on the shoulder.
When I measure a new Lapua case with the Whidden Gunworks Shoulder Bump Gauge .350 I get a reading of 1.190" to base
and with the Sinclair Shoulder Bump Gage 30A I get 1.127". That's .063" difference between the gages and looking at the
SAMMI 6.5 Grendel drawing it shows the shoulder length of 1.220 -7.
What am I missing here?