is using small rifle primers in 40 S&W safe?

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helz_mcfugly

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I have loaded my first 100 rounds of 40 S&W using small rifle primers (because thats all I had and they fit perfect) and have fired 10 of them so far that went through my glock 22 perfect. when i went to the reloading store today the guy there said "YOU DID WHAT?!?!" like I had just pulled a pin out of a live granade. but he has givin me bad advice in the past so I take what he says with a grain of salt. I have messured the firing caps of both the small rifle and the small pistol which I didnt have at the time but do now and they are exact down to the thousandth of an inch in length and width. my question is, are they the same primer just in a different box? He told me there was more pressure coming from the rifle primer and could damage my gun. any input would be nice. :confused:
 
probably wont damage anything but has way more compound and "pop" than you need in a handgun.

the only thing it might do is similar to the 209 primer in a black powder rifle. the extra ooomph can somewhat dislodge the projectile, thus leading to decreased accuracy. i imagine the same might hold true in handguns (especially non crimped straight walled).
 
it will probably raise the pressure of your loads. at least that is what i have read. they have a lot longer hotter duration flame front than pistol primers. if you loaded them hot, you might want to think about putting them in the "redo" pile. and start over with the right components. if you feel lucky, say your prayers, and bump up your life insurance before you touch them off.
 
My understanding is that if you use a hotter primer you need to back off the powder charge by about 10% and work it back up. Using the wrong components usually results in bad things happening, but sometimes you can get away with it. Any time you change ANY component you need to work it back up from the start load, even if it is just a new batch of primers or a new lot of powder.
 
I used hotter primers in a loading (I was young and an adult helped me) a long time back. He under-loaded the rounds and worked his way up.

Nothing bad happened and all the rounds shot as normal.
 
Keep in mind rifle primers are about .002" taller than pistol primers and are hotter.
I doubt .002" will make much difference but it could.
I have used small rifle primers when loading for my GP 100 and they worked fine.
 
Since you don't say how much of which powder you are using, which bullet type and weight you are using, which SR primer you are using, and what method you used to arrive at the load, it is virtually impossible to say whether it's safe or not.

Ignoring the possible size difference and even the definite heat/flame difference between a SP and a SR primer, the primer cup metal in a rifle is also a little thicker (harder to indent) than a pistol primer. Your Glock obviously works well with the primers, but a different pistol might be marginal. If you load only for the Glock that works, that is not a problem.

It's a good thing you didn't load any CF rifle rounds with small pistol primers "because that's all you had."


h_mcf's signature said:
I shoot at someone every morning. If I dont know why, they do.
Huh??
 
I wouldn't use rifle primers... as some others have mentioned, they are a bit taller than pistol primers... could lead to firing out of battery, etc... not a good idea.
 
My understanding is it is safe as long as you start low and work the load up. You can't substitute a SR primer for a SP primer with the same charge. I have some friends that only buy rifle primers and load all of their rifle and pistols with them.
Rusty
 
It won't hurt a thing if you work your load up with them. If you were not loading max loads, they won't be a problem, but why do it if you can find the right primer. Stock up so you aren't caught without them again. ;)
 
Small pistol & small rifle primers are the same size. Small rifle can be substituded for small pistol IF a load is worked up carefully. Generally small pistol CANNOT be used in a rifle load as the cup is softer and can cause a pierced primer. Regarding large pistol and large rifle yes they are different heights. The large rifle is taller which could cause slam fires in a pistol. NOT GOOD
 
well I just finished off the 100 rounds of 180 grain 40 S&W that had rifle primers in them through my Glock 22 and they shot perfect. just as accurate as my normal loads. I had them loaded with 4.5 grains of tight group. 4.7 being the max on hodgdons website. so there ya have it.
 
JCWIT has it right!
I have been loading WSR primers in.40 for the past 11 years with absolutely no problems.
It cuts down on your inventory control problems.
Now large rifle primers can not be substituted for large pistol at any time.
There is a definite height difference.
Rich
 
About the only thing small rifle primers in a pistol will do is make them super hot max loads extra super hot (now that's like pulling the pin on a grenade and playing hot potato), that's if the firing pin has enough punch to set them off reliably.
Different story for large rifle primers in pistol cases though, they sit above the casehead and if used in a lever rifle or any rifle with a tube magazine then ya have the same issue as using pointed bullets with it.
 
IPSC shooters have been loading sm. rifle primers in .38 super since light bullets were determined to be the hot ticket to making the comps work better. the cups are harder thus reducing flow back into the firing pin hole. Any modern gun should ignite them without problems. Also it might be desirable to use them if you are loading light bullets to high velocities i.e. 135 gr.
 
IF your striker has sufficent energy to set them off, there is absolutely no reason not to use small rifle primers instead of small pistol.

However, that is the ONLY such swap/switch that would be ok, due to the dimension and cup differences as mentioned above.

There is as much "heat" difference between different brands of primers as there is between rifle and pistol primers. It's not true to automatically say rifle primers are "hotter" than pistol primers.
 
thanks you. this could save me from having to buy two bulk loads of primers and only have to buy one bulk of small rifle when i stock up on supplies. I only load .223, .40 S&W 38/357 for now and the small rifle primers work great in all of them and if it makes the pistol a tad hotter I can just load my pistol loads at their minimum load and still have the same accuracy at the range. But Ill be loading .45 ACP soon and those take large pistol so im going to have to buy two bulks of primers, but still better then 3 when they are $28 a thousand. less money I have to spend at one time.
 
I use rifle primers in my level 3 loads in my 44-40 and 32-20 in hunting loads . The primer are harder and thick and hold up in high pressue loads but they are a little higher and hard to seat flush . 40SW is one cal that should not be played with . There lots of gun in 40SW don't like reloads , there alot of unsupported barrels out there . The 40SW works on mag pressues and the case is the weak link . So if you reseach the 40SW you will think twice before playing with undeveloped loads . The 40SW don't hold much powder so it goes from mild to wild in a heart beat . You must have a late model Glock the older ones are unsupported and would be in many pieces when you get them too hot .
 
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Gosh. I have small rifle, small rifle mag, small rifle match, large rifle, large rifle mag, small pistol, large pistol, and large pistol mag primers. :uhoh: :rolleyes: :D

It's a good thing you didn't load any CF rifle rounds with small pistol primers "because that's all you had."
Yep. :)
 
CF? WTH!! all these abbreviations are hard to keep up with. What does CF stand for carn founded?
 
SR primers are harder and you wont see pressure signs at the same pressure you would with standard pistol. That said, magnums would be useful for cold weather shooting or when trying to use slower burning powders more efficiently (e.g. compressed blue dot loads with 115 gr 9mm or maxed longshot loads with 135 gr .40 noslers). As mentioned, start the loads 10% below the documented starting load and use a chronograph to identify when your velocity (i.e. estimated pressure) is in the right range.
 
CF? WTH!! all these abbreviations are hard to keep up with. What does CF stand for carn founded?

everybody know cf stands for carbon fiber. get with the program.


p.s. ups lost my package today because they are retards. so tell heath dont sweat the tubes. my bet is he gets them before ups could find their (three lettered word) with both hands.
 
2 guys I shoot with on a regular basis use small rifle primers for their 40S&W loads. They are harder you you may need a heavier spring, and obviously you'll need to adjust your powder accordingly but besides that they seem gtg to me
 
yea my nephew has a Smith & Wesson M&P .40. I let him run a clip of my laods that have the SR primers in em and he had 2 out of 10 that didnt fire. My Glock 22 loves them. but I am out fo them now and have the correct primers so I guess we are done here. but lots of good info. thanks
 
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