Need help with a M4 mount hole dimensions

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Cav Trooper
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Need help with a M4 mount hole dimensions

Post by Cav Trooper » April 24th, 2018, 2:46 pm

Help, does anyone have a copy of the MWO or just drawing of mounting hole pattern and dimensions for the M4 mount for a M151a2? My floor has holes in it but I want to make sure they are correct before either saving them or welding them up and redrilling for an M4 mount when I can afford one.

Thanks,
Cav Trooper

m3a1
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Re: Need help with a M4 mount hole dimensions

Post by m3a1 » April 24th, 2018, 3:56 pm

Look underneath your truck. There, you will find the little L-shaped reinforcing brackets that are placed there for this very purpose and this may not be exactly what you want to hear but if the bolt holes are generally centered in those reinforcing brackets you are A-OK.

Dimensions are -
front bolts side-to-side 10"
rear bolts side to side 8 1/2"
front bolts to rear bolts 6 1/2"

This forms a keystone shaped pattern.

Keep in mind, I'm measuring TDC on my bolt heads and I have used slightly undersized bolts which is really necessary to make the fine adjustments and have everything bolt up correctly..

Each side of the riser should have at least one slotted hole that will also allow some adjustment.

Cheers,
TJ
Last edited by m3a1 on April 24th, 2018, 7:48 pm, edited 1 time in total.

rickf
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Re: Need help with a M4 mount hole dimensions

Post by rickf » April 24th, 2018, 4:53 pm

And the floor should have dimples where the holes go so those measurements that TJ gave you should either line up with holes or four dimples of they are in the wrong spot. Now, That said I was once told by an old very weathered sergeant that they would mount the pedestal further to the rear since if you ever had to shoot towards the rear you could not aim the gun, their was nowhere to put your arse! So if your holes are further back than the dimples that may be why. I don't really think they gave a rats arse about the reinforcements, It was not their vehicle and they were not going to be living with it for very long.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

m3a1
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Re: Need help with a M4 mount hole dimensions

Post by m3a1 » April 24th, 2018, 7:50 pm

If you need further help with this I'm sure at least one of the guys will take measurements between the dimples and provide them to you here on the forum.

Cav Trooper
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Re: Need help with a M4 mount hole dimensions

Post by Cav Trooper » April 25th, 2018, 7:43 am

Thanks all, that is what I needed. Body is being restored and has holes but they might not be correct ones. If not, they will get welded up and I'll drill new when I can find and afford an M4 mount.

CT

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