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Mossberg 4x4 .300 win mag Misfire

I have a Mossberg 4x4 in .300 Win Mag and I have been experiencing misfires. The problem occurs with factory loads (Winchester Super X) as well as shells I have reloaded. If I take the gun from my house and go immediately to the range and shoot I do not have issues, but if I go into the woods to hunt and sit on stand for a couple of hours (25-45 degrees F) then the gun misfires. I was able to get a second attempt at one of the deer and the gun fired perfectly. I have contacted Mossberg and they want me to return the gun for a technical diagnostic and have even stated that there has been a headspacing issue with Winchester ammo.

I experienced a misfire the very first time I tried to fire the rifle, but it has performed well all other times as long as I shoot it within 15 minutes of leaving my home. Is it possible that the colder weather is causing some parts to contract and this is causing my misfires? I have contemplated removing the bolt and placing it in the freezer to see if this shows me anything.
 
This is the first I've heard of the issue, but if there is already a potential head-spacing issue I can see where a rapid change in temperature could have some effect. I'd get back in touch with Mossberg to send it in for the diagnostic and ask them to send you a call-tag to cover shipping.

Keep us posted...
 
I have a 4x4 in .25-06, I've had a bunch of misfires using Winchester Supreme Ballistic Silvertips...

Some light primer his, others "look" like they should be hit gard enough to fire, but they didn't...

I've requested a return shipping label from Mossberg.....

It might be ammo related, but I should be able to shoot any factory ammo....

Smitty
 
Welcome to the Mossberg Owners Forum mossberg in tn !!

Sounds like you may have a headspace problem with the Winchester ammo. Have you tried other facotry ammo and gotten the same results !? Cold weather can affect a firearm...but I would return the firearm to Mossberg before second guessing any solution.
 
I returned the rifle to Mossberg and received it back on Saturday, Dec 10. I had marked the bolt to see if they would replace it, but I received the same bolt and barrel assembly with a new stock. No notes were included with the rifle, but I did contact Mossberg and I was told that the bolt cut-out was not deep enough to allow the bolt to fully close.

I placed the bolt in my deepfreeze for several hours, to eliminate any possible firing pin issues, and took the rifle to the field. It fired perfectly for all 10 shots and returned to the great performance I had received before. The gun zeroed very good at 200 yards (all shots in a 1 1/2" ring), I just need to regain confidence in it.

I have shot the Winchester shells in my Remington 700 as well as my Howa 1500 with no issues.

Maybe the new stock will solve my problems.

Thanks for the ideas and suggestions and I will keep everyone informed on this gun's performance.
 
Unfortunately my misfiring issue has returned. My gun performed flawlessly until I headed out to Colorado for a Mule Deer hunt earlier this month. I fired several rounds at the range before leaving for Colorado, and had absolutely no issues and I even visited a firing range in Colorado to verify that nothing had changed during the drive out. I fired 10 rounds at the Colorado range with no issues and my confidence in the gun was back to where it should be.

On the fourth day of my hunt, a nice Muley buck presented a shot at 315 yards. I steadied my rifle on my shooting sticks, and then it happened again "SNAP". Fortunately I was able to recover, cycled the bolt, and made a good shot at 305 yards.

Upon returning to Tennessee I again contacted Mossberg and asked to speak to someone in management, or at least a person with a little bit of authority. I spoke with a gentleman by the name of Joe Zakher who instructed me to again return my rifle for testing and analysis. This is the second time I have returned my gun; the third time that my gun has misfired while I was trying to take a buck, and I can't tell you how many times it misfired at the range prior to the initial return.

Not sure what the diagnosis will be this time, but I am really disappointed with this gun.
 
I hate to see your issue hasn't been resolved.

Stay on the service center. I would request details of your service and/or repair before they return your rifle. Ask to speak to as many supervisors as it takes, but don't let them return your rifle without documentation of what steps they took to make sure your issue is permanently resolved. Our board owner will be hand delivering letters from our membership to Mossberg's management at the upcoming SHOT show if you're interested in expressing your disappointment and concerns on paper. Here's the thread he started...

Letters to Mossberg...

Best of luck to you and keep us posted...
 
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