500 Magnum squib

[Broc]

Partial burn will do that

Third option - low bullet tension from a bad or no crimp.
Magnum powders need a lot of pressure to burn properly so if the bullet releases and jumps the gap before the pressure gets high enough the burn extinguishes at the cylinder gap.

Had a similar problem in 38spl with thin walled brass and slightly undersized plated bullets.
Change to thick walled brass - no issues
357 brass - no issues (firing in a 357 the 38 case created a 0.1" jump)
Cast bullet the same weight - no issues

With 500 magnum I'd assume the recoil would easily start a weakly crimped bullet moving forward reducing initial pressure even further.

Every time I search reloading data for a magnum caliber I always come across the crimping conversation and bullet jump.

I haven't experienced it, but I read enough about it when I started reloading that I make sure my bullets have proper crimp. I did check them in the beginning (shooting 3 rounds then looking at the last two).

 

[Road_Clam]

I don't normally download, as I primarily stick to the caliber's full intended potential . On the rare circumstances I do download my go-to is Alliant 2400 . Highly versatile powder for wide rangers of charges.

 

[Rob Boudrie]

I always use rifle primers in 500 S&W loads. The powder was H4227. A regular primer didn't ignite it reliably.

If the primer pocket is deep enough for rifle primers, I would expect that large pistol primers would not seat deeply enough to assure reliable ignition. Primers can absorb energy being pushed deeper into the pocket when there is a gap between the edge of the primer cup and the case. It's not like small rifle/small pistol where they can be uses somewhat interchangeably (note I said "somewhat")

 

[For Sale]

Nope. 33 grains of H110. It's not a super hot load or anything, but not light either. When I *did* have a light load (an accident, but I caught it, and fired it anyway to see what it was like) it fired just fine other than being light.

I used 40.5 grains of H110 in the 500 mag and got the same results, bullet entered the barrel and blocked the cylinder, tapped it with a brass rod so easy to get it all out. I think I have bad primers. I tried pulling the bullets on a few but with this cartridge it is harder. I am giving all the rounds away to anyone who wants to salvage the 200 Starline shells or i will drop them at the PD or a gun range to recycle

 

[Stee]

IN MY 460 I use nothing but LGR Mag primers 200 gr ftx with 45.5 gr of h110

 

[For Sale]

IN MY 460 I use nothing but LGR Mag primers 200 gr ftx with 45.5 gr of h110

My manual lists my 40.5 grains as mid load and 45 grains as MAX on H110 with the 350 gr Berry Bullets Jacketed

 

[Stee]

max for 200 gr is 46.5 h110 I shot a one inch group at 100 yrds with it, very happy

 

[For Sale]

I won;t ask what primers you are using because I purchased from an online retailer and they came as the white box OEM CCI LRM

 

[Stee]

I use federal lr mag primers

 

[NH Phantom]

I used 40.5 grains of H110 in the 500 mag and got the same results, bullet entered the barrel and blocked the cylinder, tapped it with a brass rod so easy to get it all out. I think I have bad primers. I tried pulling the bullets on a few but with this cartridge it is harder. I am giving all the rounds away to anyone who wants to salvage the 200 Starline shells or i will drop them at the PD or a gun range to recycle

Interested in that brass and some other stuff you have for sale sent PM

 

[For Sale]

So everyone is aware- doing some research I found out it was not the primers. It was the powder.

 

[DW357]

So everyone is aware- doing some research I found out it was not the primers. It was the powder.

Did you already sell the primers?

 

[For Sale]

Did you already sell the primers?

Actually I have not

 

[NH Phantom]

If the primer pocket is deep enough for rifle primers, I would expect that large pistol primers would not seat deeply enough to assure reliable ignition. Primers can absorb energy being pushed deeper into the pocket when there is a gap between the edge of the primer cup and the case. It's not like small rifle/small pistol where they can be uses somewhat interchangeably (note I said "somewhat")

Read this somewhere today
STARLINE BRASS UNPRIMED CASES 500 S&W STAR500SWEUP STAR500SWEUP- The Initial run of 500 SW Mag R cases was built to use large pistol primer per Smith Wesson and Corbon specifications. On July 28 2003 Smith Wesson and Corbon changed specification of primer pocket to be large rifle. Rifle primers are same diameter as pistol except they are approximately .006 taller. This was done to prevent primer from being pierced by firing pin when loaded with max loads and heavy bullets bullets over 400 grains."

 

[For Sale]

Read this somewhere today
STARLINE BRASS UNPRIMED CASES 500 S&W STAR500SWEUP STAR500SWEUP- The Initial run of 500 SW Mag R cases was built to use large pistol primer per Smith Wesson and Corbon specifications. On July 28 2003 Smith Wesson and Corbon changed specification of primer pocket to be large rifle. Rifle primers are same diameter as pistol except they are approximately .006 taller. This was done to prevent primer from being pierced by firing pin when loaded with max loads and heavy bullets bullets over 400 grains."

Correct- very old news....Since 2003 it is use of Large Rifle or Large Rifle Magnum primers

 

[Broc]

So everyone is aware- doing some research I found out it was not the primers. It was the powder.

What powder were you using and what happened?

You can't leave us hanging, we need details.

 

[Broc]

IN MY 460 I use nothing but LGR Mag primers 200 gr ftx with 45.5 gr of h110

I don't know what the "G" stands for. But I interchange LRM and LR primers in my 460, 45/78, 458 win mag ... no problems. Don't even notice the difference.

NOTE: Always follow your reloading manual.