Suffolk Rifle shortened MP15-22 with/without over-barrel mod

[Tomo]

I bought a short barrelled MP15-22 from Suffolk Rifles last April. Easily my favourite .22LR, it's perfect for practical shooting ( I came 6th with it in this years UKPSA postal league comp - previous best was 14th) and just as accurate as the longer versions. I've never used a moderator with it so can't comment on that. Service from Suffolk Rifles was faultless.

[nickb834]

Even though the results speak volumes (15-22 Reliability and accuracy) I just don't like the look of the mags and the design of the ejection port, the missing forward assis - it just doesn't look right to my eyes.

I should really get over myself and swap my CMMG for a 15-22 but I just can't bring myself to do it (to be fair - I've needed the working fwd assist on my CMMG, well, because it's a CMMG and I've had a load of trouble with it till I swapped to Lantac mags).

[bradaz11]

Even though the results speak volumes (15-22 Reliability and accuracy) I just don't like the look of the mags and the design of the ejection port, the missing forward assis - it just doesn't look right to my eyes.
.

they look like colt 635 uppers :)

[Tomo]

Even though the results speak volumes (15-22 Reliability and accuracy) I just don't like the look of the mags and the design of the ejection port, the missing forward assis - it just doesn't look right to my eyes.

I should really get over myself and swap my CMMG for a 15-22 but I just can't bring myself to do it (to be fair - I've needed the working fwd assist on my CMMG, well, because it's a CMMG and I've had a load of trouble with it till I swapped to Lantac mags).

I suppose it all comes down to what you intend to use the rifle for, just plinking at the range or practical / comp shooting instead.

I too prefer the looks of the CMMG rifles over the MP15-22's , however I've seen most of the CMMG owners at my club struggle with reliability issues while all of the Smith & Wesson owners hardly ever seemed to have a problem. So when it came to picking a rifle for practical shooting (when you need whatever your shooting to work 99.9% of the time) the decison was an easy one to make.

[Mattnall]

(to be fair - I've needed the working fwd assist on my CMMG, well, because it's a CMMG and I've had a load of trouble with it till I swapped to Lantac mags).

I wouldn't advise using a forward assist on a rim-fire round at any time.
If it is stuck then there is a problem that could only get worse if trying to force it in causes it to fire.

[AR15]

Nothing wrong with using a forward assist on a rimfire at all as long as its used properly.

[nickb834]

e it all comes down to what you intend to use the rifle for, just plinking at the range or practical / comp shooting instead.

I too prefer the looks of the CMMG rifles over the MP15-22's , however I've seen most of the CMMG owners at my club struggle with reliability issues while all of the Smith & Wesson owners hardly ever seemed to have a problem. So when it came to picking a rifle for practical shooting (when you need whatever your shooting to work 99.9% of the time) the decison was an easy one to make.

Yep absolutely, that's why I use my Umarex MP5 (ie not the GSG one) for mini comps - it absolutely never misses a beat and it's so pointable. I too have had massive trouble with my CMMG (until I switched to Lantac mags and prior to that started running it a bit wet - ooer). There's a couple of threads on here I started on that exact subject.

[nickb834]

I wouldn't advise using a forward assist on a rim-fire round at any time.
If it is stuck then there is a problem that could only get worse if trying to force it in causes it to fire.

There's nowt wrong with using a forward assist on a rimfire when you know what the problem is - for eg:

* stiff mags that don't always allow the first round to chamber when fully loaded; ie the 2nd round is pushed up against the first firm enough that the bolt stops in it's tracks
* if it's a case of it hasn't gone quite into battery (be it centrefire or rim fire) such that it's clearly not massively out of line
* it's just a gun full of filth - then there's absolutely nothing wrong with forward assist.

I do know what you're getting at with it being rimfire - but common sense prevails, there are times when FA is ok and times when it isn't - it's down to me to know when that is.

I don't want to type a fully internet forum level of proof as to an exact s.o.p for when it's ok and not to use a forward assist on a 22 rimfire - but I'm sure we can agree that it doesn't need to be a blanket "NO"

Cheers

Nick

[nickb834]

Nothing wrong with using a forward assist on a rimfire at all as long as its used properly.

What he said!

[AR15]

Yes, its nice to see a bit of common sense prevailing :)

Having built, test fired and subsequently fettled (thats actual fetteling like machining bolt faces, feed ramps etc..) well over 250 rimfire ARs I can tell you that the majority of the jams are caused by deformation of the soft bullet as it enters the chamber, in varying degrees of severity.

Presuming that the chamber itself is not damaged or out of spec btw.

The cause of this is mostly the angle that the round is presented to the chamber. While contributing factors to that presented angle ar many, some of the most obvious are feedramps and bolt face issues.
Feedramp and follower issues being very common in CMMGs crap mags.

The least severe situation is a scuffing of the driving bands on the bullet from them rubbing the lower third (or less) of the chamber mouth, that results in an out of shape bulge that causes the round to incompletely feed into the chamber. in this instance pushing (NOT HAMMERING) the forward assist results in a round safely going into battery with absolutely no issues whatsoever.

It should be pointed out that the CMMG chamber and feed ramp is not as well designed in this regard as the old Spikes Rifles.

Deformation of the bullet can also occure when the nose hits the top of the chamber and creates a sort of chisel cut or bend that in turn creates bulging or alters the bullet seating angle in relation to the case.
Basically if you can see the round semi chambered (brass case partly in the chamber NOT just the nose and the more case in the better) its a safe bet that it will go all the way home with some gentle pressure on the forward assist, 1, 2 or 3 presses should suffice.
If not then manual extraction will be required.
Now I dont recommeng hammering the forward assist but in the situation above, there is no reason why it would set the round off from doing so.
You are after all using the entire bolt face with quite a lot of surface area to do the work.

The bolt just dumped all its energy into the back of the case when it jammed it in the first place and I have never seen a round go off in that situation.
If you fired the gun on a jam of this nature then the hammer just smacked the back of the bolt and subsequently the bolt face into the case too.

Observation is key, if you are presented with a bent nose stove pipe (nose in chamber) then its pointless to attempt to use the forward assist and manual extraction will be necessary. In fact its quite possible to set the round off by smashing the bolt face into the angled case rim and crushing it against the feed ramp and or breech face without checking the situation.

So if you want to use your forward assist then check the feed issue first to establish if its of any use and safe to proceed.

Its saved me a load of time and effort when I have been stood in a freezing field with 30+ CMMG rifles to test fire and check.

If your rifle continually fails to feed then there is a fundamental problem with it that needs addressing, stemming from mags or bolt / breech/ chamber issues etc etc etc...