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Hello there, I’ve started assembling a couple of test rounds to familiarise myself with my Lee Precision single stage press and equipment. I’m trying to understand the different operations required and the principles to assembling the cartridges correctly before adding primers and powder to the equation.

I sized, trimmed the case to 1.145” and expanded the case mouth to receive the bullet.

I’ve got some GM Hardcast Lead RN-FP 158gr bullets that have a crimping groove. If I seat the bullet to the centre of the crimping groove this make the COL 1.425”.

Is this an acceptable COL?

The COL could vary between 1.415” to 1.435” depending on the case trimmed length (as per SAAMI) but these lengths seem to be under the COL suggested in different reloading manuals using a ‘similar’ 158gr bullet.

Any thoughts ? Should I forget the crimping groove and seat the bullet to the stated COL ?

Many thanks in advance for your replies and advice.
Best regards.

Just bear in mind that a wadcutter sits flush with the case mouth so COL is not all that important in my opinion

If they fit the firearm you are good to go.

COL with 38spl is more to do with revolvers is my understanding, as it will headspace on the rim in your rifle. as long as it feeds from your mag tube properly (more an issue on 1873 clones) and isn't jammed into the rifling, you'll be fine. I tend to seat to just below the crimp cannelure, getting the crimp die to bring the case nicely flush when factory crimped.

If you are loading for a 38/357 underlever using 38 cases its not an issue just seat to the crimp groove.