BCG question

**jsta5.56shooter** · 08-25-07, 13:33

lubricating bolt and carrier last night,noticed the carrier and bolt were magnetized. is this normal? funny, i never noticed this before. i assembled this rifle fired and cleaned it during some 3 or 4 hundred rounds and just noticed it last night.

**xm15** · 08-26-07, 23:24

this is "MPI"
it just wasn't completely de-magnetized after the check
just means it's "better" or actually has been checked for flaws

**120mm** · 08-27-07, 01:02

It's "possible" for a magnetized bcg to attract ferrous-based filings, which will accelerate wear. If it bothers you, find a place that does MPI, (aka "Magna-flux") such as an engine shop, or ask a local mechanic where he gets HIS MPI done, and they can "degauss" the BCG for you. It should only take a moment, (He finds out the orientation of the magentism, and passes the part through a strong magnetic field in the opposite direction) and the machinist should have an instrument that will tell if the degaussing "took".

It's also possible for a bcg to get magnetized during the forging process.

Either way, it's not a difficult thing to get taken care of, if it bugs ya.

**Shihan** · 08-27-07, 02:31

Or do what I would and just send it bake to the manufactuer and have them take care of it for you.

**jsta5.56shooter** · 08-27-07, 04:35

thanx for the input guys,as i said, it wasnt like that when i received it from Del-Ton,i wonder how this happens.

**120mm** · 08-27-07, 08:21

If it wasn't this way before, I imagine it became magnetized by being exposed to a strong EMF (Electro-Magnetic Field). It's also possible for ferrous metals to become magnetized by pressure, or, I think by exposure to certain kinds of material(???)

(I'm basing this on Airframe and Powerplant mechanics school from years ago. Certain materials become magnetic in the presence of other materials, I think.)

Do you store your rifle near a strong Electro-magnetic field? Like something that uses a transformer, like a computer? Or perhaps you laid it near an operating car alternator.

Either way, I don't think it's a "send it back to the manufacturer to get it fixed" thing. That would be akin to sending my rifle back to Del Ton because it's out of ammo. And like I said, degaussing is easy and quick.

**jsta5.56shooter** · 08-27-07, 19:56

ok,just talked to Tony at Del-Ton,he was at a loss also but he looked at a few test rifles at his place and it would seem that this is happening in his rifles too.
Not quite as strong as mine(i can pick up the firing pin with the small tube on the bolt) but to some extent just the same. Just for s-its and giggles , you guys give it a look-see and tell us if its there too?

**toddackerman** · 08-29-07, 13:40

Originally Posted by jsta5.56shooter

lubricating bolt and carrier last night,noticed the carrier and bolt were magnetized. is this normal? funny, i never noticed this before. i assembled this rifle fired and cleaned it during some 3 or 4 hundred rounds and just noticed it last night.

They're steel my friend and therefore magnetic. Something like Titanium wouldn't be but it would'nt old up to the abuse of the paltform.