Fitting a MK18 type RIS to a TM SOPMOD

[Andrew March]

Having a few issues fitting a MK18 to a TM SOPMOD, seems there is a lot of barrel wobble after fitting, has anyone had any experience fitting this type of RIS to a recoil gun and can they gice some tips on how they kept the rigidity in the barrel.

Cheers

[Identiti]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Ive not got experience with recoils but should be the same as any other M4 platform out there.

Providing the barrel nut is done up all the way correctly, and depending on how loose the barrel is with it done up properly.

There are barrel spacers available to put on before the barrel nut goes on, and just space it out enough so it doesnt wobble or move.

With doing that though you may well end up with a slight gap between the reciever and RIS

Hope that helps

[Andrew March]

Re: Fitting a MK18 type RIS to a TM SOPMOD

No, it's not the same. The TM recoil platform has a completely different delta assembly and a three quarter slip on lug that keep the barrel in place but you can't use the lug with a MK18 barrel nut as it inteferes with it when you start tightening it.

[Identiti]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Ahh okay i get what you mean with the lugs from older rifles ive worked in mostly TM and ICS.

Just another idea then as its last thing i can think of at the moment, is to modify the old delta ring nut to be used with the MK18 if thats something your able to do your self. As thats possible to do just means you wont have a delta to revert back to how it was if you decided too

[Andrew March]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Not sure even that's possible to be honest, the new TM system is a right royal pain, with a three part delta ring arrangement then another outer sleeve that screws onto the barrel holding the delta assembly in place.

[murta369]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Do you mean a DD block 2 rail or KAS RIS that was issued with the original MK18

[Andrew March]

Re: Fitting a MK18 type RIS to a TM SOPMOD

It's a DD rail, 9.5", not sure if it's a block 2, it's the one where you can take off the lower half by taking out the screws on the sides and mount a barrel mounted 203.

[Mightymage]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Ok well you will firstly need a one piece outer barrel. I also reccommend the Laylax sopmod armorer wrench to really get the locking ring tight.

You will then need to put a barrel shim on the outer barrel to stop it from wobbling. As there is no front sight/gas block there is nothing holding it in so a shim will be needed to let the locking ring clamp down hard.

For my recoil all i needed was a barrel shim to get rid of the wobble!

[Black Templar]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Or just use a bit of black tape to pad it. Had the same issue, worked fine.

[B.E.N.]

Re: Fitting a MK18 type RIS to a TM SOPMOD

Shims are the key!

[badger906]

Re: Fitting a MK18 type RIS to a TM SOPMOD

i had a similar issue with a Madbull Daniel Defense front end, i made some shims (out of RC car piston sleeve shims) which i glued together and then stuck to the inside of the delta ring/nut. It packed out the space stopping all excess wobble.

[Clot]

Re: Fitting a MK18 type RIS to a TM SOPMOD

I had the exact same issue.
It took me a few days of swearing, cutting my wrists on a bench grinder, loads of grinding and fileing.

I had to shave the lock nut down, and then pack it out with tape to get it to sit centred.
Took me a while to suss it out, but the poster a few up says he just used tape.. wish I got that idea before I went to town on it!

[Black Templar]

Sweet!

It worked for me.


Sent from my iPad with due wonder that I've helped out.