Mossberg 4x4 Bolt Action Troubleshooting

I tend to agree. I am not a fan of the weaver bases on my .338. I'm switching to a one piece bridge mount that I'll be getting for x-mas. :mrgreen:

I just got my 4x4 in 30-06 today and I ran a patch as i always do to get any grease or grit out. The manual has a check to make sure the safety works and all which involves dry firing which I did, then ran the bolt in and out a bunch. Nice trigger by the way. The problem is when I put an empty case in to see how it extracts, the first time was fine, but the second the bolt wont close or open. The handle moves about 20 degrees and there is a slight rotation in the bolt and it is completely open to the left as the lug is hitting metal where i can see, but it will not pull back. It only closes about 20 degrees from open. I tried tapping a rod into the case but didnt want to pound it. I put a lot of force on the bolt handle thinking it was just new but NOTHING. I just removed the action from my 6 hour old unfired gun to ship back to Mossberg as it is an expensive club. Before i ship this back to be fixed, is there something Im missing? Ive had Remington 700s all my life and maybe Im just blind to something but I can usually fix about anything Ive had go wrong in 35 years of shooting and this will be my first return for service in over 200 guns. I saw some posts about sticking bolts so maybe its that, but it cycled fine with that same case 1 minute earlier. The case has a spent primer in it by the way and i use it like a dummy round to check extracting as in, see how far it tosses the empty and where before i go to the range. Any ideas?????

Welcome aboard Sir.

I've got a suspicion that your issue and most of the other 'sticky' bolt issues on the 4x4 are related to out of spec or poorly fitted bolt stops/assemblies ref. part #'s 2, 3, and 4 on your user manual...

I read where maybe some Junk/grease in firing pins/bolts
Well I have 3 Trophy Hunters and 1 4x4 in 30-06 with the Old style trigger.
I found that the firing pins in my 3 Trophy Hunter rifles are Smaller in Diamenter then the 4x4 .
The pins are around 1/8 inch on the ATRs and Larger on the 4x4 around 3/16 inch then tapers to about 1/8 in
Trophy Hunter 308 Win BA369859 small pin LBA New trigger with Mag
Trophy Hunter 243 Win BA356809 small pin LBA New trigger Blind Mag
Trophy Hunter 30-06 Springfield BA 355524 small pin LBA New Trigger With Mag

4x4 30-06 BA089073 Old Trigger Large Pin

I guess if there are Trophy Hunters are they ATR ? With or without Det Mags?

I spoke with Mossberg about a Walnut stock for My 308 with Det Mag it is a Dicks Model
The booklet with the rifle says 4x4

Valmet, you took a fired brass case which was fired from a different rifle and chambered it in you new rifle, right? I suspect the rifle which fired the case has slightly more headspace than your new Mossberg. When you closed the bolt on the case, it put a lot of pressure against the shoulder of the case and the extractor of your Mossberg bolt shaved off some brass. When you extracted the case, that brass shaving fell just behind the chamber into the cavity where the bolt lugs engage. I suspect that is now binding the bolt head and preventing it from closing. Basically, I think it's something just behind the barrel which is preventing the bolt from going far enough forward to rotate all the way down into firing position. Check with a flashlight and spray some Windex in there and blow it out with compressed air (or keyboard duster can) to hopefully remove whatever is there.

I always Full Resize New Brass and sometimes have to cut them shorter.

The firing pin hole may need cleaned inside the bolt and the very end of the bolt head may have grease/dirt/machine flakes metal on it .The firing pin has a step on it and stops at the face of the bolt head. Dirt/grease could stop the pin from striking the primer hard
I cleaned and used a little oil on 5 of my rifles. Also check the cam where the firing pin rides and stops at the rear of the bolt. clean and use some oil there.

I would also check and see if the sear is releasing in the trigger and not draging on the bolt sear
Also have the headspace checked if the chamber is too deep this Will case misfires But will cause the primers to back out of the fired case.

hello everybody i am new here but i have a question, iwas deer hunting with 3 friends 2 week ago in canada,1 of my friend just purchase a mossberg 4+4 in 300 win mag,here the problem we were walking to are blind he had his rifle sling over his sholder as we walk we did not notice the bolt open and the bullit was ejected from the rifle,after noticing it, i look at his rifle after you chamber a round the bolt is so easy to open i have a feeling that not normal,it more easy to open with a round in the chamber then without one,my friend is worry the bolt might open with the recoil of the shot also what if he see a deer en route to his blind,thank you for your time.

I know this is a little old post
But where the cases once fired for a Different Rifle?
They will need to be Resized .