I was just wondering if the great minds of AR15.com could tell me what the $100 & $200 difference is between these three bolt/carrier assemblies? JP interprises & DPMS chrome
http://www.jamdreams.com/midwest/jp1.jpg
info: http://www.jprifles.com/OperatingSystem.shtml
LTM seen here: http://www.ar15.com/forums/topic.html?b=7&f=22&t=174224

Please don't flame me for "not just using a standard" setup, but I really don't understand the big difference.  I can read til the cows come home but I need some "real" info on the usefulness/difference in the prices.  I'm leaning towards the JP but please inform me.  Thanks guys

Looks to me like you are comparing a stock item std. bolt carrier with some plating on it to a custom made sold stailess carrier. One can chip and flake and rust and one can not.

thanks but I know that the chrome "could" chip but if you read the question again you'll see I asked about the 3, JP, DPMS, and LTM.  The design is different (at least visually) on all three.  HELP inform me of the "not so obvious" differences guys.  Thanks again

OK hard chrome wont chip if done propperly.  You could bend the carrier and it would not flake or chip.  How is it the inside of the carrier does not chip or flake and neither does the barrel or chamber but exposed hard chrome with lots of lube and little no bearing surfaces on it flakes?  Thats not the issue.  If you do some reaseach you will find no other part or weapon has this wives tale of flaking hard chrome so ingrained as the M16/AR15.

The JP carrier is aluminum and way too loght and it will increase the cyclic rate.  Its the perfect item to slip in your buddies rifle if you want to laugh as he has malfuctions and cant figure out why.  Unless you are shooting light loads in a dedicated varmit/match rifle it has no use.  Next is the DPMS unit.  One of the worst machined factory hard chromed units you can buy.  They have been known to not properly heat rteat the parts after hard chroming.  This causes hydrogen enbrittlement and the bolt breaks at the cam pin hole.  Did I mention the machining was ugly?  The LMT has an extra gas port for use with carbine gas systems.  The bolt is covered with electroless nickle and designed to not foul as much and take longer to break the lugs and wear out the extractor springs.  Essentially its a SOPMOD 2 bloc upgrade for the M4.  Its not been adopted (KAC will have a unit to compete and possibyl other companies) but its probably the best bolt and carrier you can put in your rifle at this time.

It seems to me if those are your choices you only have 1 choice.  The Young Mfg. carrier or Les Baer unit (same thing) would be a decent second option for a more current instead of future design bolt/carrier.  

DevL,

The pictured JP bolt carrier is [b]NOT[/b] aluminum.  

JP builds two different bolt carriers: (1) an aluminum low-mass bolt carrier, and (2) a stainless steel "tactical" bolt carrier.

They emphasize use of the SS bolt carrier on their rifles for duty use, and the low-mass Al bolt carrier for competition-only use.

With regard to use purpose of the low-mass bolt carrier, yes, it would be useful in a varmint rig, but the real purpose is for IPSC/3Gun-style action shooting where you want minimal gun movement due to the mass of the bolt carrier slamming rearward and forward, e.g. so you can double-tap something at 50 or 100 yards faster.

FWIW, my JP CTR-02 came with the low-mass aluminum bolt carrier and I've had absolutely no malfunctions or failures so far.  The gun does move less with the low-mass carrier installed.  

Note that you may have to use a different recoil & buffer setup with the low-mass carrier.  See JP's web site for details, or just call them if you're having trouble with it.

-z

Zak,
I think it is worth mentioning that the JP rifles come with an adjustable gas system.  I have heard that is important when using the LMOS bcg.  Their SS BCG should work well in any AR though.  You don't run your CTR LMOS with the gas full open do you?  Honestly curious.

atrdriver1,

They do have adjustable gas systems.  There is a screw in the gas block which constricts the gas flow into the tube.

I haven't adjusted mine open all the way yet to see what happens.  Someone over on the BrianEnos.Com forums probably has tried it.

-z

First I want to thank you guys, I have learned already more then I had hoped.  I always saw the DPMS in guns and figured it had to be the "good shit" but even if it isn't as bad as DevL says it is out of the ranks for me now.  I think I'll keep on the path of the JP TOC.  Keep the reviews and info coming guys.  Thanks again

For comparison,
JP low-mass bolt carrier (with LMT bolt):
[img]http://www.demigod.org/~zak/DigiCam/2003-ar15-bolts/small/IMG_0189.jpg[/img]

Rock River standard bolt carrier assembly:
[img]http://www.demigod.org/~zak/DigiCam/2003-ar15-bolts/small/IMG_0190.jpg[/img]

LMT bolt carrier:
[img]http://www.demigod.org/~zak/DigiCam/2003-ar15-bolts/small/IMG_0191.jpg[/img]

-z

I have not had the opportunity to handle the JP stainless unit so I cant comment.  I would not dismiss the LMT unit unless the price bugs you.

The JP TOC (pictured in Mrrogers1 first post) is about $170 for just the bolt carrier - no bolt included.  Add $46 for the complete assembly ($216) including bolt.

The LMT bolt carrier is around $100.  The complete LMT bolt assembly from MSTN is $285.

The LMT bolt alone is $185.

The Les Baer chromed bolt carrier is $98.

So the JP bolt carrier is the most expensive carrier in this discussion - about $70 more expensive than the LMT carrier.

I have not handled the JP TOC carrier, but I have the three I pictured.  Based on my experience with JP stuff, I would expect the JP TOC carrier to have a superior finish, including the smoothness of the contact surfaces, to the LMT unit.

The LMT bolt, on the other hand, is going to have some obvious advantages over the standard bolt.  The extra-power extractor is worth its price, alone.

The most expensive choice would be the JP TOC and the LMT bolt, and I'm going to try that on my next rifle.   I'm not convinced the LMT carrier buys you much over standard, quality, bolt carrier [<- edit] in a mid-length or rifle-length gas system.  Comments?

-z

LMT bolt will still be more corrosion resistant than evena hard chromed bolt.  It will still have a longer service life.  It will still deal with more fouling.  The only part that has to do with carbine vs rifle gas system is the carrier.

Yes, sorry, I was referring to bolt carriers in my last sentence, and I just editited it to make it more clear.

Re: bolts, The LMT bolt is clearly superior.

Back to the bolt carriers:   Does the LMT bolt carrier have any advantage over the other bolt carriers (box stock RR included) for mid or full gas systems?

thanks
Zak

Heck with it all, I like the LBC carrier (for semi-auto use).  It's exquisitely machined, and again after it has been chromed to maintain specs, and as heavy as an M16 carrier.  I like it better than the LMT carrier (which I have as well) though I use the LBC with an LMT bolt now.

The JP SS I have not had experience with, and it has it's own design features so it's hard to compare, but otherwise I think the LBC rules (except in M16's then it's the LMT)