I saw on BookFace that Bloke on the Range just won an auction for a BMS CAM rifle.  A bolt action rifle in production since 1980 that uses an AR15 bolt, barrel and magazine.  I have seen UK legal "AR15" rifles without gas systems that have a side charging handle.   

This is my question for the collective.  If you wanted to build a straight pull rifle using  primarily AR parts for 5.56 or 7.62 based calibers, is there any need for a recoil spring or even the rear half of the bolt carrier?  You need part of it to cock the hammer when cycling the rifle, but is anything else actually necessary?  Since there is no gas system and running the BCG forward cams the bolt to a locked position, why include them?  It seems to me that some interesting precision rifles could be made relatively cheaply.

Original Post

The system would need a detent to prevent the bolt from traveling to the rear under accidental impacts. Or possibly a lever that could pivot up to lock the BCG forward for most carry. Other than that, you are on track for a simple system.

I like where your head is at.

Longeye posted:

The system would need a detent to prevent the bolt from traveling to the rear under accidental impacts. Or possibly a lever that could pivot up to lock the BCG forward for most carry. Other than that, you are on track for a simple system.

I like where your head is at.

Maybe a shorter "recoil" spring that just keeps the bolt closed.  Not a long enough, or strong enough spring to make the bolt strip a round from the magazine on it's own, but enough to resist some accidental movement to the rear.  Also not long enough that anything has to extend beyond the receiver.

The side charging handle could perform this function. As you pulled it, it would cam out the detent then release the bolt to be pulled to the rear. Say, .10" of handle movement would disengage the detent. When the bolt was returned forward the detent would drop back into place.

I've been thinking of this for a while.  No gas block, gas tube, buffer, you could lose the back half of the bolt carrier.  You could make a super light rifle with a folding stock.

Has the Troy Straight Pull actually been released? Have not seen any. Was always interested in a Lantac Straight pull, but I don't think they ever released it for the US market. 

Dorsai posted:

I saw on BookFace that Bloke on the Range just won an auction for a BMS CAM rifle.  A bolt action rifle in production since 1980 that uses an AR15 bolt, barrel and magazine.  I have seen UK legal "AR15" rifles without gas systems that have a side charging handle.   

This is my question for the collective.  If you wanted to build a straight pull rifle using  primarily AR parts for 5.56 or 7.62 based calibers, is there any need for a recoil spring or even the rear half of the bolt carrier?  You need part of it to cock the hammer when cycling the rifle, but is anything else actually necessary?  Since there is no gas system and running the BCG forward cams the bolt to a locked position, why include them?  It seems to me that some interesting precision rifles could be made relatively cheaply.

Just to have an AR-15 hybrid/bastard that you have to manually cycle?  Wouldn't a free floated barrel on a T/C Encore be cheaper?

It still wouldn't be THAT accurate with the slop in the BCG, Bolt lock up with the barrel chamber and of course the constant change of magazine tension from rounds stripped off on the underside of the BCG.

Basically: Lipstick on a pig for the sake of it being based on an AR-15 platform.

Spend the money, get a solid AR and work up custom loads for it.  For the best accuracy: single load rounds with a magazine well adapter.

 

Dorsai posted:

That Troy rifle is nice.  Now I'd like to see it 6.5 Creedmor suppressed for long range.  Would it equal a conventional bolt action in accuracy?

Even with a good trigger group; you're still behind the curve of most decent bolt gun (striker) triggers since you're a slave to the traditional swinging hammer design with 3-4x longer lock time.

While you've eliminated the gas block, you still have the contend with the aluminum receiver/barrel nut/rail interface where some may not handle the torque as well as others.  While actions/chassis and receivers for bolt guns differ; they are generally less touchy about super heavy bipod loading and aggressive pressures being applied to the gun as an AR can.

Could you pull some great groups under good conditions...probably?  Will it beat a bolt gun under all the bolt gun conditions?...highly doubtful.

 

And while I know some SASS dudes can run the hell out of a lever, is the pump not traditionally the fastest of the manual actions (Pump > Lever > Bolt) in that respect?  Thus, making the least crappy version to replace a semi AR?

  That being said, I'm highly skeptical of the dynamic of manually operating an AR bolt that much faster/better with your "off" hand  MORE EFFICIENTLY than a good bolt with a practiced hand if it's a question of filling a precision rifle role.  

Last edited by Community Member
Wild_Willie posted:
Dorsai posted:

I saw on BookFace that Bloke on the Range just won an auction for a BMS CAM rifle.  A bolt action rifle in production since 1980 that uses an AR15 bolt, barrel and magazine.  I have seen UK legal "AR15" rifles without gas systems that have a side charging handle.   

This is my question for the collective.  If you wanted to build a straight pull rifle using  primarily AR parts for 5.56 or 7.62 based calibers, is there any need for a recoil spring or even the rear half of the bolt carrier?  You need part of it to cock the hammer when cycling the rifle, but is anything else actually necessary?  Since there is no gas system and running the BCG forward cams the bolt to a locked position, why include them?  It seems to me that some interesting precision rifles could be made relatively cheaply.

Just to have an AR-15 hybrid/bastard that you have to manually cycle?  Wouldn't a free floated barrel on a T/C Encore be cheaper?

It still wouldn't be THAT accurate with the slop in the BCG, Bolt lock up with the barrel chamber and of course the constant change of magazine tension from rounds stripped off on the underside of the BCG.

Basically: Lipstick on a pig for the sake of it being based on an AR-15 platform.

Spend the money, get a solid AR and work up custom loads for it.  For the best accuracy: single load rounds with a magazine well adapter.

 

So it's possible to get  >.5moa out of it then? I've shot some Larue wares that will do that with a "sloppy  bolt" all day long. 

M. Wilson posted: 

So it's possible to get  >.5moa out of it then? I've shot some Larue wares that will do that with a "sloppy  bolt" all day long. 

100% it is POSSIBLE.  Repeatable...?  Reliable...?  Me personally I say: Doubtful.  

Just hearing the madness out of the Army's Marksmanship Unit with their armorers fine tuning those weapons!  Gah.  No thanks.

But again, its for a PURPOSE of using issued weapons and FINE TUNING the bejeesus nuts out of them into precision sticks.

Again, if MISSION DRIVES THE GEAR and someone wants REPEATABLE ACCURACY for the life of the weapon, then why not a precision bolt gun?

It could be done CHEAPER & BETTER than a manual cycle AR platform or proprietary AR platform.

Yes there are some folks that make some FINE AR's, I am a HUGE fan of KAC SR-25 goodness myself.  I have gotten to hang with some folks who wring every once of goodness out of them. 

But to have a manual cycle rack grade AR...?  For what...?  What is the ROLE?

Shits n Giggles.  Check.  Got it.

 

Why.  First, I was speculating after having seen what the Brits are shooting because they can't get semi-autos.  Second, the straight pull Swiss rifles (K31, Schmidt-Rubin 1911) have a good reputation for fast handling and very good accuracy.  Straight pull rifles have a tendency to run faster than a conventional bolt action.  Good barrels, receivers, triggers, etc. are readily available and well tested.  Same for furniture.  For about 5 seconds I thought about the advantage when running suppressors, but concluded that other than gas in the face, it really doesn't have any advantages there.  As was mentioned, there are people who want something for a ban state.  A straight pull AR15 might be as fast or faster than a lever action, with the advantage of detachable magazines.  I went a different route for trips to CA and built up a rifle on the Fightlite receiver that uses a modified bolt carrier and conventional sporting stock.  Consequently, I could build a "featureless" rifle and use detachable magazines without having to go through their bullet button contortions.  Someone else may want to go the straight pull route instead so getting some discussion, feedback, ideas could be useful to the members.

I hear you DORSAI and thanks for explaining it for the crayon eater: ME. 

I am planning a move to Hawaii which is a wicked ban state, but, even that "feature" wouldn't help there as their laws specify greater than 10 round magazines in rifle or pistol and not 'semi-automatic' dependent.

I just get amazed at SOME of the innovation when people start adapting the older AR design, instead of looking at other options or purposely designed features that are more suitable to task and purpose.

Hence why there are more & better weapon choices than just AR's.

Especially true under SOCOM!   

 

Last edited by Community Member

I know Lantac used to make a dedicated strait pull bolt, I know nothing other than stumbling across pictures but it may give you ideas. The strait pull design was mildly intriguing to me as something with better ergonomics for a pistol build. I really like the idea of a pork sword pistol build but not keen on their stock design and the strait pull came up as I was researching options. I know nothing about them other then the video/article but it may give you some ideas. 

https://www.range365(dot)com/super-light-and-cheap-300blk-ar-pistol-build/

 

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