Merits of Middy, Intermediate, or Gas in SPR

[BrigandTwoFour]

Hey all, leave it to BRD to make me start planning my next build when I haven't even finished the current one.

My current build is a 16" "battle" rifle with all the most reliable parts I could find. However, I would also like to assemble an SPR "for my girlfriend."

My choices have basically worked down to a Noveske 18" (intermediate gas), Rainier Ultramatch (18.5" middy), or Centurion DMR (18" Rifle).

The accuracy difference between these three is negligible to me as all three are likely to produce devastating results far better than either of us can shoot.

With that in mind, what real functional difference between the three should I be looking for? I've always read that a rifle length gas system is the most reliable, and possibly softest shooting- but is that really the case? Would it be noticeable enough to warrant over the ease of cleaning on the ratchet/polygonal rifling of the other two options?

[ALCOAR]

If one is more reliable than the others....no one has certainly to my knowledge shown it to be so w. supporting facts/evidence. I personally have a MRP SPR that is a mid length and i guess perhaps its a little smoother but not that much to sway me from not going w. say a carbine gas system for that fact alone.

In your case....it really should only matter in respect to your rail selection and whether or not on your build you want a gas block exposed or not.
For ex. if you like a 10" rail lets say and you want to hide the GB...then you can find a real reason for actually picking one gas length over the other.

[Belmont31R]

Yes a rifle length gas is going to be slightly softer but not much.



I just assembled a Mk12 w/ Centurion barrel, and between the Ops Inc & rifle length gas theres hardly any recoil at all. Very smooth gun....at 100yrds when shooting off the bench with a bipod the crosshairs move maybe 6" between shots. Easy to do double taps like this on steel gongs, and have both shots off before you hear the 1st tink...


Accuracy is very good between the barrels you mentioned, and another case of can't go wrong between them.

[BrigandTwoFour]

Through some of the searches I did, I read that a rifle gas system doesn't have enough dwell time on an 18" barrel. The MK12 uses it because the addition of a suppressor increases the required dwell time for the action to cycle properly.

For those of you who have used a rifle-length system on an 18" SPR, have you seen any issues like this?

I do live in the northern tier, and will be shooting quite a bit in cold weather. I don't know how much difference that makes, but I figured I should mention it.

[BrigandTwoFour]

If one is more reliable than the others....no one has certainly to my knowledge shown it to be so w. supporting facts/evidence. I personally have a MRP SPR that is a mid length and i guess perhaps its a little smoother but not that much to sway me from not going w. say a carbine gas system for that fact alone.

In your case....it really should only matter in respect to your rail selection and whether or not on your build you want a gas block exposed or not.
For ex. if you like a 10" rail lets say and you want to hide the GB...then you can find a real reason for actually picking one gas length over the other.

The reliability factor I mentioned wasn't so much about going bang every time. In some of the discussions I've seen here, some have mentioned that because rifle systems are easier on components, there is generally less wear & tear (like broken bolts, for examples).

I would probably be leaning towards a 14" rail on this build.

[Belmont31R]

Through some of the searches I did, I read that a rifle gas system doesn't have enough dwell time on an 18" barrel. The MK12 uses it because the addition of a suppressor increases the required dwell time for the action to cycle properly.

For those of you who have used a rifle-length system on an 18" SPR, have you seen any issues like this?

I do live in the northern tier, and will be shooting quite a bit in cold weather. I don't know how much difference that makes, but I figured I should mention it.



I just got my MK12 last week and only have a few hundred rounds through it but I havent heard of any reliability problems shooting the SPR barrels without a can. In fact I don't think most people are using cans on their builds.


If you go to the custom build forum there is a thread stickied at the top for the Centurion Mk12.