In previous articles we talked about the importance of bolt gap on delayed roller blowback rifles like the CETME or the HK G3s. We even touched on how to increase bolt gap by adding oversized rollers to correct wear of internal parts.
What we did not do is give instructions for replacing the rollers. Now, as I have said before, I am not a gunsmith, but I will present an easy way of changing rollers. You don’t need much in the way of tools – a pair of pliers, a roll pin punch (I used a nail) and a hammer.
- First ensure you have NO ammunition in the room. This is imperative to make a habit whenever you are cleaning, working on, or dry firing your firearm.
- Next strip the rifle (we have an article on that)
- Remove bolt assembly by twisting – you probably can do this without tools if you have decent hand strength
- Remove Bolt head from Carrier (twist and pull)
- On the top of the bolt head you will see a small hole with a roll pin. Using a small punch tap out the roll pin, I did not have a punch nearby that was the right size so I used a small finishing nail. Retainer plate and rollers will now slide out the side
- Shake bolt head until the roll pin falls out.
- Insert your plus sized rollers on the retainer plate (one side of the roller ill have a small divot in the center. This divot corresponds to a tip on the retainer plate.
- Slide retainer plate and rollers back in the bolt.
- Reinstall pin (may take a tap on the punch with a small hammer)
- Reassemble firearm function check to ensure you put everything back properly
- Check bolt gap (it should have increased) If it has not or it is still out of specification you may have to consider getting the barrel repressed – there are not a lot of gunsmiths that are willing to do this, but luckily I found two in my area.
Once again for resources (I am not paid to say this)
I buy my rollers from RTG International Surplus Parts in Arizona
And for barrel work, I use wither Dave’s Gun shop in Cookeville TN (I’ve been in firearms classes with Terry their gunsmith – great bunch of guys)
Or Lock Stock and Barrel in Franklin TN (sorry no website)