SBRing an M85 PAP; how to drill rear trunion/plate to mount folding stock??

[cobber]

I finally got my stamp and eagerly proceeded with mounting the folding stock.

I find, however, that my Hitachi hand drill is not making any headway with the rear trunion/plate on the M85. I'm about halfway through on the first of two holes and just seem to be polishing metal now. Using titanium coated bits.

Is this just too big a job for an electric hand drill?

Argh.

 

[2ADMNLOVER]

Is this just too big a job for an electric hand drill?

Argh.

Nope , but you will eat some bits in the process .

 

[cobber]

Nope , but you will eat some bits in the process .

Thanks!

Three down. Halfway through the first hole. Wow, guess I have led a sheltered life, never having drilled steel before...

 

[vitamink]

If it has the under folder trunion it'll be a mother to drill through. I don't know steel could be that hard. The pistol trunion is way easier.

 

[cobber]

If it has the under folder trunion it'll be a mother to drill through. I don't know steel could be that hard. The pistol trunion is way easier.

It's the side folder. I think the bolts will have pretty good purchase once the holes are tapped. (I thought the metal would be too thin. Silly me!)

 

[Sling10mm]

Are you running the drill in reverse?

Sorry, couldn't resist...

 

[cobber]

Are you running the drill in reverse?

Sorry, couldn't resist...

Yeah, I double checked just in case.

Just ordered a gross of bits. Not gonna give up!!

 

[freekforge]

Is the drill upside down in the chuck? we actually had a kid do that in the shop

Use lots of oil and use only sharp drills. It can be quite the female dog.

 

[1911ly]

Drill only fast enough to see chips fly. 400-500 rpm max and use cutting fluid/oil. Using high a speed will quickly dull a bit.

Your location is not in profile. You might get someone to volunteer a drill press or a mill if we new your location.

 

[1911ly]

Is the drill upside down in the chuck? we actually had a kid do that in the shop

Use lots of oil and use only sharp drills. It can be quite the female dog.

Are you fessing up to a oops Ethan!

 

[duffman0286]

May i recommend using hardened drill bits preferably carbide but cobalt works great as well and use a cutting oil to remove heat! (if it stops smoking add more oil !!!!) cobalt bits are easy to find at nearly any hardware store. slow speeds are key! and don't start too large! use a a number of smaller bits first and slowly work your way up ( not only will you save bits you will drill cleaner holes with less breakage)

 

[cobber]

Thanks for all the suggestions. This ought to keep me busy until Christmas!

 

[Slow Hand]

I drilled mine with little issue! I used a VZ-58 side folder so I drilled and tapped for a 3/8" bolt in the center, but also put a 10-32 machine screw to help keep it from rotating. I didn't feel like messing with getting it locked down in the drill press so I just used my DeWalt cordless.

Hope the second hole goes easier for you!!

 

[cobber]

I drilled mine with little issue! I used a VZ-58 side folder so I drilled and tapped for a 3/8" bolt in the center, but also put a 10-32 machine screw to help keep it from rotating. I didn't feel like messing with getting it locked down in the drill press so I just used my DeWalt cordless.

Hope the second hole goes easier for you!!

Must be softer than the stuff I'm struggling with. My cordless would have no effect at all...

 

[engineerpower]

If you can't get a bit to bite regardless of what you do, the metal is hardened and you'll either need machine-shop equipment, or will have to anneal the steel. Since you're going at this with a hand-drill, I wouldn't recommend that you take a torch to your receiver...

 

[Squirt239]

Bring it by the shop. I'll drill it out with the mill. Probably take less than a few minutes.

 

[engineerpower]

Brett, just thinking about how to properly set it up on the mill. I don't know how to do it on a vertical right off without either the barrel interfering with the knee, head hitting the table, or the receiver standing a couple feet over the table. Does your mill have enough clearance to rotate the head 90°? I can get about 70-75° on my Index.

I need to come visit your shop sometime...

 

[1988-4551]

second on cobalt bits

 

[cobber]

Bring it by the shop. I'll drill it out with the mill. Probably take less than a few minutes.

Thanks. Should have waited for your offer, but got her done. When I slowed down the drill, I got a lot more metal out, which seems counter-intuitive.

The two holes are not quite level, but the folder plate still squares up with the receiver.

I'll have to post photos shortly. I find that I don't need the extension for good cheek weld. Also not crazy about the Magpul front grip, but I'll give it a chance.