Minimum and maximum dimensions of primer pockets

Elric

Well-Known Member
https://ballistictools.com/articles/primer-pocket-depth-and-diameter.php

Primer pocket dimensions and tolerances

Sz Depth- Depth+ Dia - Dia +
Sm 0.1170 0.1230 0.1730 0.1745
LR 0.1250 0.1320 0.2085 0.2100
LP 0.1170 0.1230 0.2085 0.2100


Primer dimensions and tolerances

Sz Hgt. - Hgt. + Dia - Dia +
Sm 0.1150 0.1260 0.1745 0.1765
LR 0.1230 0.1360 0.2105 0.2130
LP 0.1150 0.1260 0.2100 0.2120


NOTE: "Sz" means Size
NOTE: "Sm" means Small Rifle / Small Pistol, dimensionally identical
NOTE: "-" means Minimum
NOTE: "+" means Maximum

"It's interesting to note that while small pistol and small rifle primers are exactly the same size, the same is not true of large pistol vs large rifle. I have heard of people substituting small pistol and small rifle primers during desperate times, but one should always be careful of pressure increases and the potential for pierced primers if one resorts to such extreme measures. It's always best to use components as they were intended.

Another notable fact is the overlap in tolerances. The largest primer is taller than the shallowest pocket, and the loosest in-spec pocket is the same size as the smallest in-spec primer. It's for these reasons that we sometimes run into so much frustration with certain brands of brass and primers."

So that's what my K&N Uniformer does.
Large Pistol – Primer Pocket Correction Tool
Large Pistol set to .122″ depth

LR 0.1230 0.1360, huh, that suggests a .013 difference. And that depends on the lot tolerances / make of the primer itself. Inquiring minds wonder what the Winchester WLR actual sizes are. Especially if one had 5K WLR and a lot less WLP...
 
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Elric

Well-Known Member
PRIMERS AND PRESSURE by James Calhoon

Here it is.

To me, I think the anvil height is the wild card. It seems as if the WLR cup height would fit, but I measured some 44 Mag brass, the pockets were .114-.117, so it depends...
 
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