Small primers

[Rcd567]

Bought 500 round of mixed brass.  Guy sent 550 because there was some small primers mixed in.  63 to be exact.
Question, is there an advantage to small primers?  I have several boxes of Federal 200 grain HST ammo.  They appear to be all small primer.  What gives?

[The_Shadow]

Originally the small primers were being used in the brass as "NT" Non Toxic primers were being used for indoor range use!
The good thing is with primer shortages, it can help loading if you have one or the other...

[RDub01]

A few years ago, I noticed .45 ACP ammo had small primers. Given the relatively small amount of propellent needing to be ignited, it doesn't seem to make any difference. Seeing .45 ammo with small primers after decades with large primers was very weird indeed. Recently I've come across 10mm brass with small pockets as well. Might be a trend coming...

[CtYankee]

I've compared identical loads across my chronograph and didn't see any significant difference between large and small primers.

[Rcd567]

Ok, kind of makes sense.  Trust me, I'll load these but I'll use a hand primer or load them at the end as I don't want to change up the priming system in my progressive for 63 cases.  I've still got a thousand to load.

[Sailormilan2]

Load some of the Small Primer brass with Small Rifle primers and compare the two. I?ve heard some thoughts that the use of SRPs may result in less primer cratering. I have no personal experience with that as I haven?t located enough Small Primer 10mm brass to use.

[sqlbullet]

Every time I look in my supply closet and see all the small rifle primers I have, I think I just wanna get small primer pocket everything except maybe the big magnum rifle cartridges.

[John A.]

^This  What sqlbullet said.

I have about 50 small primer 10mm brass that my friend gave me when I was first getting into the 10mm.  I am pretty sure they are cci brass.

[redial]

Small primer 10 or 45 brass often makes me say bad words when humming along on my Dillon. I thought I found ALL of 'em. Damn!

[Markwell]

      With .45ACP and 10mm I sort the SP brass and load it up for "field ammo" to be used when brass recovery is not possible.  It just goes away but some still manages to find it's way home to F#*% up the progressive loading process.

[mr.revolverguy]

CTYankee your results are definitely different than mine


Full Review https://dayattherange.com/?p=10235

[The_Shadow]

mr.revolverguy did some great testing!  Thanks for the range testing and reporting!

[crkckr]

The differences in mrrevolverguy's and CTYankee data might be type of bullet or powder.  Some powders can vary a lot in how they burn after they are ignited.  Even things like total charge and percent of case filled can have an effect.  However, there shouldn't be any huge differences.  In some cases the use of magnum primers might be called for but I would be at least cautious if using rifle primers simply because the cups are generally thicker and might hide pressure signs.  Maybe.  I don't know they would for certain and if they do, how much pressure they might mask.  Personally, I would stick with magnum pistol primers and save the rifle primers for the AR!
Cheers,
crkckr