500 SW Mag reloading issues...please help

[dgarvin1]

Hello,
I have a SW 500 mag with a 4" bbl. My handloads misfire fairly frequently. When I say misfire, I mean that the primer is fully contacted and dented and there is no detonation of any kind. No hangfires either.

I understand that there is confusion about large rifle vs. magnum pistol primers, but I have both types of brass and have fully experimented with both types of primers. It makes no difference. I have taken great care to clean the primer pockets, allowing for maximum primer seating depth, but this doesn't seem to make a difference either.

At first I thought there were issues as follows:
1. The primers are not appropriate for this load. However, I've experimented with Winchester and Remington primers in all combinations and it doesn't make a difference. I have not tried other brands though, mainly because I have zero misfires with any of my other handloads.

2. There is a defect with the gun. However, it shoots factory ammo just fine.

I have been reloading for 20+ years and I reload for 15 different calibers across all types of actions and systems. I don't think I'm an expert, but I'm pretty experienced. My other handloads work great, so I'm really at a loss!

Has anyone experienced this issue with their 500 mag, and found a resolution? I am being driven mad by this! I simply can't figure out what the heck is going on!!

Any help or insight would be appreciated. Thanks.
--DG

 

[nambu1]

You may have a batch of bad primers.

 

[Grumulkin]

I have a S&W 460V that doesn't like CCI primers; I think they're just a little too hard. It does fine with Federal primers and everything else I've tried.

Since you're tried two different batches of primers, I don't think it's the primers per se.

 

[Mr.Revolverguy]

I have an alaskan 454 that does the same thing. After much experimenting I found this. Now this was 5 years ago according to the notes I took then. I don't think the cup hardness has changed much which I believe is what your running into here.

454 Alaskan
Shoots all factory ammo just fine

Reloads with Wolf primers (40% failure to go off on first shot 2nd shot 100% success)

Reloads with Remington primers (20% failure to go off on first shot, 2nd shot 100% success)

Reloads with Winchester primers (100% success rate)
Reloads with Federal primers (100% success rate)

Reloads with CCI primers (75% failure rate to go off on 1st shot, 10% failure rate to go off on 2nd shot, 3rd shot typically ignites them.

So here is what I have done. For all of my semi auto rifle reloading I use CCI primers which I have no issues with in rifle. After 18 years of reloading no slam fires has occurred. In my bolt actions I use whatever I have on hand.

In 500S&W and 460S&W I use Winchester large rifle with 100% success rate.

In 454 I use Winchester small rifle magnum 100% success rate

In 44mag I use Winchester large pistol 100% success

In all the other calibers I reload I use federal.

 

[dgarvin1]

On the right track...

Revolver guy...your notes about the Alaskan are similar to my notes on my 500.

I think I need to try some different primers...maybe some Federals.

Any more comments, please keep them coming folks!! Any intelligence I can get would be extremely helpful.

Thanks a lot for posting!

 

[FROGO207]

I load for a NEF Handi Rifle and use LRM primers now. The hammer has a heavy strike and I have used CCI, Win, Fed and Rem. All have worked well for me but the LR primers will sometimes be erratic though they all lit off OK. I would always use magnum primers if for nothing else than eliminating erratic ignition problems if it were me. In my auto loading pistols the Winchester primers will give the best results if they have light firing pin springs. Also CCI seem the worst (hardest) so far.

 

[Iron Sight]

I have no experience with a 500.............But check and make sure the the mainspring strain screw is tightened all the way. Tightening it on my 625 remedied/fixed a similar probem on my 625.

I cannot find a parts breakdown for a 500 but if it has one it probably is in the lower front of the grip frame. Some grips that cover the frame have to be removed to expose it.