Failue to Fire, Mossberg 500A Conversion

Gbro

New member
Last fall a very close friend and former Supervisor of mine experienced a miss-fire(failure to fire main charge) with his Mossberg 500A Muzzle Loader conversion. This is a 50.cal with a .209 primer.
http://www.mossbergs.com/manuals/Muzzleloader.pdf
He was loaded with 90 grains of loose Shockeys Gold FFg. and a 300 grain Hornady SST bullet (the one w/ plastic tip).
The primer fired when he drew down on a small whitetail buck @ 55yards but the main charge failed to fire. He was able to re-prime and again the rifle failed to fire(primer fired).
Taking the rifle back to the shack Mullin's was unable to pull the load with his ball puller because of the hard plastic point on the SST bullet.
Thinking maybe the powder somehow got damp and unable to remove the breach plug on this barrel, the gun was stored close to the wood stove to try and dry out what could be wet powder.
The next day the vent hole was picked and the gun primed. Again the rifle failed to fire. (The loading rod indicated a normal hunting load) in case you are wondering.

The rifle was re-primed and failed to fire several more times and then put aside for the bench at home.

Back home Mullins soaked powder charge as best he could through the vent hole and then tried everything he could think of to remove the breach plug and was unsuccessful.
He even considered heating the barrel with the muzzle pointed in a safe direction and then elected to make a long pilot bit and guide to bore out the point on the bullet.
The ball puller did not start in the pilot hole and a 3/8 inch drill bit was machined at the shank to tightly fit inside a 3/8" steel tube and loctite'ed into place. The complete plastic tip was removed from the bullet tip and again pilot drilled for the ball puller.
This worked, however the process of working in the area of a loaded barrel was not without concerns even though the powder was possibly dampened with penetrating oil, but the ball puller could now be threaded into the bullet which pulled out easily. .
Now the lesson learned was "not" to use this kind of bullet in this firearm.

Mullins now started loading this same gun with a 360 grain Norton ball (some think this is a minie), should he ever need to pull this ball his puller should do the job at camp.
Well Mullins did again experience the same miss firing.
This time the load was the Norton ball over 2ea 50gr, 777pellets. and again his 209 federal primers that he buys 1000 at a time.
Mullins re-primed this gun 11 (ELEVEN)times and picked the vent several times, each time the 209 primer popped with the noise associated with a pre-load primer firing.
The ball was pulled and the pellets removed. He had them at his bench today when I stopped for a cup of wife's Coffee.
I have a good idea on what is happening here, The picture of the 2ea 50 gr. 777 pellets might not show just how clean the pellets are. There was no indication any priming flame ever touched these powder charges. My friend was humbled to realize these 2 powder pellets overcharged his gun.
The breach plug in this conversion has a vent hole measured @ .025"

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Shot one of these conversions when they first came out, without any problems. The 209's have had more than their share of problems and to some extent, well deserved. However, still think that they have a place in Inlines. There is a term in Pneumatics and Fluidics or if you wish plumbing. The term is "Dead-Heading", where no amount of pressure can cause a flow if their is a plug. That is what I think is happening. The spark is unable to flow to the main charge. Some work around this by loading loose or just making sure the projectile is in a non short-start condition. Just my opinion but I think your shot-string is too tight. Take and run your range rod with a moist patch down the "empty" bore, aim it in a safe direction and ignite your 209. If the rod is still in the bore, pull it and inspect your patch. You should see a good hard print all over the patch. Some folks would suggest opening up the vent and your know that can create it's own set of problems. Everybody has misfires for one reason or another. The only problems I have had is with a #11, in a sidelock with a 777 main charge. Shot the 10ML two weeks ago and it was packed heavy and tight without any misfires or hangfires. Then again, that was smokeless. By the way, the CVA Electra would never have this problem but a spare battery would be in order. Again, not my cup of tea but they are here !!! ... :rolleyes:

Be Safe !!!!
 
hmmm...

I had a very bad experience with a Mossberg 500A- the gun was 1970's vintage, but like brand new. I bought it from someone who repo'd it, in a rental apartment- it was left there- he was selling the items to recover back rent. I got it for only $100, a real deal.

Loaded it up, fired a shot, when I worked the pump to chamber another round, the gun instantly went off by itself, without pulling the trigger. Tested it again, it did it again. If I worked the slide with any force at all, it would go off- if I worked it very slowly, it would work ok with trigger.

So then I emptied gun, and worked slide hard- the firing pin dropped. I worked slide easy, and hit side of gun with my hand, firing pin went off and dry fired. Then I worked slide to recock it again, put it on SAFETY, and side of gun with my hand

much to my surprise, the gun dry fired again- it would dry fire just by hitting it, every time, with the safety on.

I called Mossberg and got a BS answer, saying "oh well it's an old gun"- I told them no, it's LIKE BRAND NEW and was not even used, and it has this hair trigger/accidental discharge problem.

upon totally disassembling the action, I found that no internal parts had been filed, no trigger job had been done- all internal parts still had the black coating on them from heat treat/bluing. Using a dremel, I did a "reverse" trigger job on it, giving it a harder trigger, then reassembled it.

Now the safety works, it doesn't go off when the slide is slammed hard, and it's a safe, reliable gun. Still have it.
 
I truely believe that the 209 has given in-line manufacturers many sleepless nights. 209's have not been that user freindly let alone trying to engineer them into various in-lines. All manufacturers have had limited success and most are still on a learning curve. Personally do not care for them as I am mostly a Traditional M/L shooter or "old school". My in-line hunter is set up with a musket primer. However, I am not critical of anyone who uses 209's. Just know they will have there share of problems to some extent. In-lines are here to stay and I suspect the same on the 209's. I read that the in-lines have over 90% of the current M/L market. Suspect this is probably true and makes me appreciate my side-cockers all the more. Most of my experiance with 209's is trying to help other folks with their problems. Have not seen any problems with the Omega family, 10ML's, H&R's and am sure there are others. Will not list the ones that I have seen problems with. Basically I do not have a problem with some 209's, just their application. :rolleyes:


Be Safe !!!
 
IMHO Inlines are cheats invented to sidestep the Muzzleloading deer season laws. I have no use for them and I would like to see them relegated to the regular gun hunting season. Notice I started this post with IMHO so take it for what you paid for it. I have no quarrel for those who own and shoot them, but no sympathy either. Traditional muzzleloaders rule!;)
 
Notice I started this post with IMHO
Been waiting for that one and have to compliment your restraint and the reality is that they are here to stay. I mostly shoot Traditionals and teach both. However, I promote Muzzleloading and they are valid. The new in-line shooters that I have seen, could give a hoot about history and traditions. It's just not their thing and that's okay. .... :rolleyes:



Be Safe!!!
 
Could we get a bigger photo?

Just let me know how and I will be happy to oblige.:)
And on dial up doing this has been hard for me. I do not know how to size the pictures properly that is why I mostly do attachments but thought bigger would be better for this:confused:.

As a Firearms Instructor I need to understand and help those using in-lines even though my muzzle loaders are all traditional.
I have a lot to learn in the in-line arena. Hey I have a lot to learn period!
My loved ones do not always follow what I like therefore I need to adjust my ways;).
I do not even offer advice to friends anymore. They look to us that have muzzle-loaders and want our opinions. Well the greatest majority have bought what I recomend(what I could hold in my hand and not feel shamefull) to not like them at all and trade them in in short order. My car-pool buddy has a beautiful Great Plains Flinter (Lefty) and loves to shoot it, however he will not hunt with it. He just isn't confident enough that it will fire when the opportunity arises. He bought an in-line for hunting, So be it:p
 
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