primer pocket for 38-40

[mrappe]

I have been shooting my 73 Whichester for CAS. It is a 38-40 and I have always used Large Rifile Primers in it since 1) I am using it in a rifle 2) Winchester developed it for the rifle and Colt used it for it's pistol so I always assumed that it would need a LR primer. The last time I bought new brass for it was 2 years ago and I got some4 Starline brass. The primers would seet but I noticed that they are not as recessed as some of my other calibers. The primer is only high enough to drive me batty. You almost have to imagine that they are high to notice. I don't think that is an issue since it is such a small amount and i always us RNFP bullets in there anyway. But I called Starline and they said that the pockets were dimentioned for a Large Pistol primer. this seems dumb to me since the caliber was originally designed for a rifle. Anyway I was thinking of using the RCBS Trimmate Lirge Rifle Pocket Uniformer to make them slightly deeper. Has anyone else had this problem?

[Montana Slim]

Well..my Pa has a pile o' 38-40's including Colt & Winchester rifles and Colt & Uberti revolvers. He's using large pistol primers (Winchester, to be exact)...with no difficulties.

If you had any revolvers in this chambering, you'd be having a fair share of problems getting them loaded 

There is certainly no need for use of rifle primers in this cartridge (38-40 is not a hot-rod round)...and I'd certaily not modify the cases (they're too valuable).

My best advice is to start using pistol primers.

Slim

[Mako]

I have been shooting my 73 Whichester for CAS. It is a 38-40 and I have always used Large Rifile Primers in it since 1) I am using it in a rifle 2) Winchester developed it for the rifle and Colt used it for it's pistol so I always assumed that it would need a LR primer. The last time I bought new brass for it was 2 years ago and I got some4 Starline brass. The primers would seet but I noticed that they are not as recessed as some of my other calibers. The primer is only high enough to drive me batty. You almost have to imagine that they are high to notice. I don't think that is an issue since it is such a small amount and i always us RNFP bullets in there anyway. But I called Starline and they said that the pockets were dimentioned for a Large Pistol primer. this seems dumb to me since the caliber was originally designed for a rifle. Anyway I was thinking of using the RCBS Trimmate Lirge Rifle Pocket Uniformer to make them slightly deeper. Has anyone else had this problem?

Mrappe,
The .38WCF and .44WCF have had Large Pistol Primer Pockets since about 1929.  Before that they had SMALL rifle primer pockets.  If you have been using rifle primers then you've just been fortunate until now.  As Montana said, if you had revolvers you would have noticed this out a long time ago. The rifle has the leverage to still function with high primers, a revolver will bind up.

These are the SAAMI specs for the primer pockets and the allowable primer heights.  I say allowable because in practice the primers intentionally are targeted and trend towards the short end and the pockets towards the deep end.

• 
  Large Pistol Primer Pockets are .117" to .123" deep
• Large Rifle Primer pocket depths are .125" to .132" deep

Large Primers have these height dimensions:

• 
  Large Pistol Primer Heights are .115" to .125" deep
• Large Rifle Primer Heights are .123" to .133" deep

So you can see that it is not wise to put a Large Rifle Primer in a pocket cut for a Large pistol primer.  They will almost always sit proud.  Primers should ideally be about .005" below the surface.

Don't make the mistake others have and assume since you are putting the .38WCF ammo in a rifle it is classified as "rifle ammunition."  In reality it's not, and it is classified as a pistol cartridge because of the pressures involved.  Just as someone shouldn't use pistol primers in a .308 Winchester case because they are using it in a Remingtom XP-100 which is a pistol, don't use rifle primers in a .38-40.

Don't cut your pockets deeper, that is a waste of time and there is no advantage in doing so.  In addition rifle primer cups are thicker and you could potentially get misfires if your firing pin was fouled.  Most lever rifles don't have a super hard firing pin strike anyway and you don't need a thick cup.

As I said, they have been this way for over 81 years, you and 99% of the shooting world just didn't realize it.

Check out this photo of some old cartridges I have.  The two center cartridges are .38WCF cartridges with the small primers the one on top has "W" on it which our resident expert "W.44WCF" tells me designates a smokeless powder load.  The one below it is a misfire that was struck several times making the deep indent. The case in the upper right is an old but less than 80 year old case with a large pistol primer instead of the small rifle primer.



My Great Uncle was the .38WCF shooter (I wish I had the rifle) and I have the .44WCF and the .45Colt the other cartridges were for.  Also note the top left .44WCF is a small primer case as well.  That rifle made in 1886 has been in the family since the 19th century.

Regards,
Mako

[August]

I cannot be much help to the O.P. as I have used large pistol primers exclusively in the 38-40 for many years.  Ignition has been 100% with pistol primers for me -- this, in race guns that are highly tuned.

[mrappe]

Thanks for the info. I originally chose LR primers because they were "Harder" than LP primers and I thought that that was what was needed. That was 14 yrs ago and like I said they wer'nt high enough to cause a problem in the old rifle. I will switch to LP primers in the future. By the way this rifle was made in 1886.

[Noz]

I called Starline a couple of years ago about the primers cups on their 38-40 and 44-40 cases. Lee reloading charts call for rifle primers on these cases.
Starline says they cut the primer pockets on these cases for the Large Pistol primers.

[Mako]

Thanks for the info. I originally chose LR primers because they were "Harder" than LP primers and I thought that that was what was needed. That was 14 yrs ago and like I said they wer'nt high enough to cause a problem in the old rifle. I will switch to LP primers in the future. By the way this rifle was made in 1886.

You won't be sorry, the best of luck to you.

By the way this rifle was made in 1886.

Maybe it's my Great Uncle's rifle!!! Actually I think he bought his in the 90's, the .44WCF was my Great Grandfather's and the three brothers started shooting '94s in .30WCF or .32 Winchester Spl about the turn of the century.  They also had '95s and were pretty progressive in some ways.  The middle one ended up being a Train Engineer and the other two went into the oil fields as roughnecks in the days they still used steam power.  They had a little money because of their jobs and they spent it on hunting and guns. One uncle had a '95 in .30-40 early on and the other a .40-72 (I know because because I still have some cartridges for it) which he later sold and bought a .30-40 like his brother.

My Grandfather primarily stuck with the '94s and later bought a '95 in .30-06. Which is a funny story because he thought he was buying a .30 Government (.30-40Krag). By this time the .30-06 "Government" was out and he bought one on the way from the oil fields in Mexico as he passed through San Antonio to meet his brothers on a hunting trip in Colorado.  When He got to the camp no one had .30-06 ammo and it took them half an hour to figure out why the .30-40s weren't clambering in the rifle.  I still don't know why  he didn't buy ammo at the hardware store in San Antonio.

On this forum we've talked about calling cartridges by the right name to avoid confusion and here is one case where two (actually 3 if you count the .30-03) .30 caliber rifle cartridges were commonly called the .30 government.  The sales guy actually may have been confused about the cartridge as well because my Grandfather told him he wanted a .30 Government like his two brothers  had and they had a .30-06 on the shelf.

The best of luck to you,
Mako