Primer pocket depth

[tomjerry1]

Alright, this is for all you smart revolver guys, I'm new to this game. I recently got a S&W 929, and never would have imagined that a pistol would be so finicky with primers. I've been shooting autos for years, and have never had the issue I'm experiencing with this revolver. It has an extended firing pin, Wilson springs, and I polished the internals with a fine india stone. It started out with a 14 lb double action trigger pull prior to the parts, and now I'm at 7.75 lb DA pull. In the beginning I was using CCI and Winchester SPP, everything ignited at 14 lb, but at 7.75, about a 25% failure to ignite. I got lucky, and a friend traded me for Federal SPP. Federal almost always ignites, down to about a 2% failure rate, I don't want to tolerate that. 

So, I read in many posts, there is such a thing as a correctly/carefully/properly primed case with Federal? I've always been under the assumption, that if the primer is seated just below the rim, this would be a seated primer.  I have checked the primer depth, .004 to .006 seated below the rim.  What is the trick to obtaining a 100% ignition?  Also, I'm using Winchester brass. 

Edited December 17, 2020 by tomjerry1
Forgot someting

[alecmc]

"full seated" is the correct answer. 

 

I've got a 1050, so I can set a consistent primer depth at .009 below flush. ( sweet zone is between 008 and 010 IMO )

 

You want to eliminate any "gap" between the flash hole on the brass and the bottom of the primer. If the firing pin needs to waste energy moving the primer fully forward before setting off its counter intuitive to what you want. Fully seat and set the hammer accordingly. 

 

Also, using the correct firing pin is pretty important. A factory pin that measures .495 will work, or buy an aftermarket pin from somebody like apex or TK.

Edited December 17, 2020 by alecmc

[Koppi]

Federal brass won't stick when ejected, win. does for me..

 

[tomjerry1]

Thanks for the fast response. I have been doing some checking, and SPP cases should be between .117 to .123" on the primer pockets depth. I have measures a handful of Winchester pockets, and they average .117" Now I measured the Federal primers, and get about .120", so I'm assuming that the primers get rolled a bit when the primer reaches the pocket depth? I haven't checked Federal brass yet, but will tomorrow. I haven't had any problems ejecting the Winchester brass, yet? 

I was wondering if people are trimming pocket depth? Something I've never concerned myself with prior to this.

Now I'm trying to figure out how to set my primers deeper, I use a 550. 

[kmc]

If you have a good trigger on your wheelgun (but not too good), the answer is simple--Federal primers + handseating each primer (following loading) = 100% ignition.

[Farmer]

Proper primer pocket depth for small primers and large pistol is .122. For large rifle it’s .131.  Problem is that on most cases the corners of the pocket have a radius. This contributes to some give, boing whatever you want to call it. When you seat a primer in a pocket that’s been uniformed there is a positive Stop when it hits bottom, and the anvil is in solid contact with the pocket. This = No wasted energy. 

[PatJones]

I load on a 550. When I first got the press, I experienced some failures to fire in my 627. Hand seating primers did help, though I chose to seat the primers before running thru the 550.

 

This year I gave up hand priming, but I've really had to pay attention to keeping the shell plate tight. I run the shell plate tight enough that it doesn't run completely smooth. It seems as though any tilt in the shell plate can lead to misfires.

 

I install the shell plate and tighten the center screw until there's drag when turning the plate. I then lightly tighten the lock screw, this makes it easier to make very small adjustments. I then loosen the shell plate retaining screw just enough to make the press useable. There's usually one spot between 2 of the 4 positions where it doesn't move smoothly, i just find the tightest adjustment i can live with.

[Toolguy]

I load on 550s, have for around 30 years. I make sure to lean forward firmly on the handle for seating every primer. Eliminates the need to hand seat. I'm running 5 to 6 LB. DA pull on most of my guns (except rimfire and carry guns).

Edited December 18, 2020 by Toolguy

[MikeyScuba]

I aim for .115

 

before my new press on my 650 I would give an extra squeeze to seat them deeper.  While I never had an issue (in practice) I would hand re-seat match rounds anyway. 

[ysrracer]

Yep, I load on either a 550 or a 750. How deep should you seat Federal Small Pistol Primers, deep.

[revoman]

Till they all go bang 100 %. Or just shoot a 627

[tomjerry1]

I guess that I'm going to have to get use to really pushing hard and living with flat primers? To get the DA pull to 7lb would be great, just have to keep on trying.

While I have your attention, I have a Speed Beez setup for moon clips, I have both Speed Beez moon clips and TK moon clips. The round hole in the TK stick to the rack with authority, and the Speed Beez stop sign shaped hole sticks, but not convincingly. Any fixes so that I can use both with confidence?

[Farmer]

Or uniform you’re pockets. 

[tomjerry1]

Ya, already planning on that project. 

[Farmer]

If you don’t have many to do it’s not too bad. But if you have several hundred it’s a real pita. I use the K&M tool in my old lathe with a heavy glove. After a couple hundred my fingers are numb and I have to stop for a while. You probably won’t have to go very far on yours, just enough to remove that radius from the corners. That usually just takes a quick zip. 

[357454]

In my years of shooting revolver I have never had to clean nor cut primer pockets for my competition loads. my presses have been a 550, 650 and now an 1100, for the 550 and 650 I seat the primers until I can feel them stop then put extra presssure on the handle until you can feel it flex slightly, this will give you .009 to .011 primer depth. The 1100 can be set to what ever depth you prefer, I seat mine to .0t0  when using federal primers for all of the calibers I shoot. 

[357454]

On 12/18/2020 at 9:53 PM, tomjerry1 said:

I guess that I'm going to have to get use to really pushing hard and living with flat primers? To get the DA pull to 7lb would be great, just have to keep on trying.

While I have your attention, I have a Speed Beez setup for moon clips, I have both Speed Beez moon clips and TK moon clips. The round hole in the TK stick to the rack with authority, and the Speed Beez stop sign shaped hole sticks, but not convincingly. Any fixes so that I can use both with confidence?

A flat primer is not a bad thing when loading for a tuned revolver, it is a visual confirmation your primers are fully seated.

[tomjerry1]

Yes I have a lot of cases to do, I use a drill press and a glove. Flat primers are something I'll have to get use to, I have been loading for 1911 style pistols for years, and flat primers would go to the practice pile. Of course, I've not loaded primers as soft as Fed SPP, nor have I ever been concerned with primer pocket depth, revolvers are another beast.

[PatJones]

If you look at an unseated primer, the anvil is just proud of the cup. If you seat the primers until the cup just touches the bottom of the primer pocket, the anvil pushes in and applies the correct amount of pressure on the primer pellet. Something like the K&M tool allows you to feel this.

 

In practice, a small bit of flattening is tolerable. It's not ideal, but it's more tolerable than a primer that is not fully seated. If you flatten the primers too much, you can crush the pellet of priming compound inside the primer. You would have to be really trying to flatten the primers too much, but just be aware that there is a point where it's excessive.

[kmc]

7 hours ago, 357454 said:

In my years of shooting revolver I have never had to clean nor cut primer pockets for my competition loads. my presses have been a 550, 650 and now an 1100, for the 550 and 650 I seat the primers until I can feel them stop then put extra presssure on the handle until you can feel it flex slightly, this will give you .009 to .011 primer depth. The 1100 can be set to what ever depth you prefer, I seat mine to .0t0  when using federal primers for all of the calibers I shoot. 

Agree, that's been my experience across 550 and 650 (and now using 1050). I always hand seat all rounds before I moon them going to a big match. If I didn't, I learned I *might* see a couple not fully seated over 350 rounds (<<1%). In other words, hand priming was mostly a waste of time but I viewed it as insurance.

[pskys2]

On 12/20/2020 at 9:37 AM, tomjerry1 said:

Yes I have a lot of cases to do, I use a drill press and a glove. Flat primers are something I'll have to get use to, I have been loading for 1911 style pistols for years, and flat primers would go to the practice pile. Of course, I've not loaded primers as soft as Fed SPP, nor have I ever been concerned with primer pocket depth, revolvers are another beast.

My Glocks, with light springs for 3 1/2# actions, definitely like Federal SPP.  I have some factory MagTech stuff that the Glocks won't set off reliably unless a heavier Striker Spring is in.  Of course my 1911 9mm needs a 19# mainspring for them too, but can use a 17# for Fed SPP.