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View Full Version : Minimi barrel life- keyholing


Iraq Ninja
10-13-09, 16:22
One of our FN Minimi barrels started to keyhole badly today. I will not have time to examine it up close till the morning. I suspect the barrel is worn out.

Anyone know what kind of round count these barrels are good for? This gun is over 4 years old. No idea on the round count through it.

http://i34.photobucket.com/albums/d127/Iraqninja/minimi.jpg
Heavy Metal
10-13-09, 17:57
This sounds like a job for Shinn Fein 1911.
Robb Jensen
10-13-09, 18:14
Or Clynch.
DMR
10-13-09, 18:22
Look at the muzzle we shot out every 249 barrel in our company in a week. The 249s were about 4 years old also and had the old style long barrels with the adjustable gas setting. We rehearsed for a congressional demo of a raid, with two platoons - on the SBF. The 249s basicly fired two+ basic loads twice a day for four days (600-800 rounds in 30 minutes.) During the actual demo two of second platoons gunners belted 800 rounds and put their guns on adverse. Both guns burst into flames when the plastic from the heat shield melted and dripped onto the barrel. I was attempting to clear a ruptured case on one when it happened. The other one had sent a round through the side of the barrel after it drooped in front of the gas block.

Any how the muzzle on the remaining 16 were slightly oval and there was no visible rifling in any of the 18. I realy need to dig out that VHS. Sorry to tell a war story instead of answering your question, but it was here or the Keating thread.
Iraqgunz
10-13-09, 20:50
I-Ninja,

I asked this same question when I was at FN and I think I was told to simply rely on the headspace and breechbore erosion gages. My guess is that if it is keyholing then it is fried.
Mongo
10-13-09, 21:44
My Stoner 63a commando barrel started key holing after about 60K rounds but when I got the barrel it already was a smooth bore for the first 2 inches so I do not know what total round count is. The barrel only began key holing when there is only the slightest trace of any rifling along the entire barrel.

http://home.comcast.net/~sfischer397/pictures/keyholes.jpg
http://home.comcast.net/~sfischer397/pictures/Stoner416-1.jpg
CarlosDJackal
10-25-09, 23:45
As badly as that Stoner is keyholing, you're lucky you're not getting any baffle strikes!! :eek:
Mongo
10-26-09, 10:00
As badly as that Stoner is keyholing, you're lucky you're not getting any baffle strikes!! :eek:

There is no can on the gun with the key holing barrel.
Failure2Stop
10-26-09, 10:19
In my experience the barrels will outlast M4/M16 barrels as long as they are treated with the proper barrel change procedures.
If barrel change procedures are not followed and a hot barrel is continually used, they will show severely shortened lives due to loss of throat, rifling, and loss of barrel heat-treat/warping.
Artos
10-26-09, 10:24
I would be curious to know what the bore looks like.
Ned Christiansen
10-26-09, 21:24
You guys obviously have not availed yourselves of the water-cooled upgrade kit.....:D
BRAAIJR
10-27-09, 08:42
Phillip Atkinson
FN Weapons Training Department
Tel: (803) 736-0522 ext 314
Fax: (803) 736-9949
E-mail: phillipa@fnmfg.com

Phil is the FN guru he knows all!
Whootsinator
10-27-09, 22:39
You guys obviously have not availed yourselves of the water-cooled upgrade kit.....:D


You mean one of these poured over the barrel? :p

http://southernfriedfatty.files.wordpress.com/2007/07/dasani.jpg