Quote from: wilsonphil on July 31, 2015, 11:29:06 AM

After wasting more time(lots of money) testing WAY to many different configs, this is my rule and I have never had a failure following this

1.  If you are running shorter than a 14" barrel then I strongly suggest piston driven.

2.  If you are running over a 14" barrel stay with the gas system.

As far as AK's go I have seen a few failures but typically not related to the design,  poor metal, ammo or just worn completely out.  Interestingly enough I have personally seen a AK re-chambered for 8mm Mauser but did not get the time to study it in detail as I had more pressing things happening around me. 


 My latest upper is a 6mm turbo which I am very happy with for the long range shooting I am doing right now, for optics I used to always buy Nightforce but they have taken some of their manufacturing over seas so I do not buy them anymore, all optics I buy now are Leupold they have the best customer service and have extremely fast turn around currently I am using a VeriX 3, 8.5 X 25 with 50mm objective and varmint reticle.  All of my current lowers start out as 80% and I truly enjoy building them, I just started to get into 1911’s and I have learned way more about 1911 than I ever wanted to know

Picture of my latest build, Coyote was taken at 350yrds, dropped instantly

Phil, nice stick and nice pelt. Genuinely curious about the short vs long point of view on piston vs gas with more detail. My LMT 10.5 gas gun eats any ammo I throw at it and never misses a beat, suppressed or not. Like Don mentioned before, a lot of guys that build their own uppers experience failures and I can only hypothesize why. Most gas SBRs reliability issues stem from the lack of appropriate sizing of the gas port and location on the barrel.

From a purely mechanical point of view the AK was designed from the beginning to be a piston gun and the bolt carrier and piston is very robust and made to fit solidly together. And the mating surface of the piston to carrier is one piece.

The AR, on the other hand has very limited room under the hand guard for a robust piece of machinery and the striking surface of the rod to the bolt carrier takes a lot of abuse, especially on auto.   (That's where most problems occur) That striking surface is bolted to the bolt carrier (in place of the original gas key) and not made integrally nor is the piston solidly mounted to the bolt carrier as it is in the AK

The failures of the piston guns have been primarily around that weakness from what I understand. I've not studied the HK, but they probably purpose built from the ground up to address that problem.

In the end, the reason many people want a piston AR is not having to deal with the carbon fouling and cleaning, or guys who run too much lube in the sand, which is just the price you pay for that system as it was designed.

Look forward to continued banter and different points of view.


Sent from my iPad using Tapatalk

Well it really comes down to reliability, a little gas dynamics and a lot to do with bullet weight, type of powder and then all kind of wonderful things happen with the bolt when you go from a gas system to piston system.  If you are shooting a heaver bullet in a gas gun then the powder has time to burn in the shorter barrel, this few mili-seconds is enough time to for the powder to fully combust and not foul the gas system, this can still be an issue in piston gun but if the port is sized correctly you won’t have the issue or is not as sensitive to the issue.  Bolt issues are the next big failure item on the piston driven system I will explain the bolt issues in a couple min.
 
 If you always run commercial quality ammo from a known source I agree you will most likely never have a problem BUT that being said you never know what you will be shooting in all cases and the weapon will fail when you need it most.  So if you run unknown ammo in a barrel shorter than 14” I highly recommend the piston system is not necessary but I don’t want a failure.

Ok lets listen to the crazy redneck that only went to the third grade for just a few seconds,
 
One of the major things is that in a gas system, when the gas pressurizes the chamber in the bolt carrier, it actually pushes the bolt forward, and that pushing of the bolt forward, as it unlocks, takes a good amount of load off the back of the locking lugs as it’s unlocking, I know this sounds counterintuitive but this is what is going on in that area.

With a piston system, as you’re pushing back on the bolt carrier, you not only have tilting pressure which is uneven, it’s pulling the bolt backwards, which adds more load to the locking lugs of the bolt as the bolt carrier’s going to the rear, and the faster you drive it to the rear, the worse off it is. If you use an M4/AR15 in its conventional barrel length, which is 14-1/2 inches(16 for the civilians of course), I don’t think a piston gives you any advantage over a gas impingement gun. I think that an M4 in a 14-1/2 inch barrel military configuration it is just as reliable as a piston gun with the 14-1/2 inch barrel. The piston driven in this configuration will give/develop different problems.

It really comes down to time the bolt/carrier is under pressure, if you are able to have the luxury of having a barrel with 7 or more inches of barrel in front of the gas port, it gets the job done before the bullet leaves the end of the barrel. When you go to a 10-inch barrel or an 11-1/2 inch barrel, that time significantly drops, along with your reliability. The only way to do that is to open up the gas port, and you get a big gulp of air immediately. The rifle becomes sporadic at that point. The advantage on a piston system might come in with a shorter barrel.
If you look at the bolt carrier velocity, and you shoot ten rounds with a gas system, and you look at the velocity and you look at the standard deviation of that velocity, the standard deviation, meaning the velocities, and you overlay those velocity curves over the top of each other, the gas impingement system is much, much more concise and reliable than the velocity is for a piston-driven AR type rifle. The piston-driven gun is all over the place as far as its bolt carrier velocity, and its bolt carrier velocity at the back of the gun. The AR system likes a gas impingement system much better when the barrels are over the 14”, because it’s a much better utilization of the gas.

Do you get what I am saying?  Or do you think I am a fruit loop

I hate when local stores don't stock what we need. But check these out....I sent a email regarding availability and cost.

http://www.hstc.com/Products/OrdnanceProducts/SepBolts/

Hey Norm,

Most likely won't sell them to you, the way things are now unless you have a big government contract they won't even talk to you.  But it never hurts to ask.  And a hand full should only cost you a few years pay!

Ok not lot to report on the RC, its been running very well.  I had a small issue with the rear springs contacting the rear spring hanger.  This was the first time I had the RC loaded up, this was with a full tank of fuel, six people and all of our paragliding equipment so it was a full load.  So to help with the issue I installed 1” longer rear shackle and that seems to of resolved the issue.

 Then I took the RC out and took it over the little course close to the house,  over looking the ocean.

Second that, like any good unit a little closed at first but once they see that you can do the job they open up.  I agree with the "standard" French military they are a little unmotivated but the pilots I worked with were top notch..  Big problem in France/Europe is its still a caste system, that drove me insane and is what I hated most when I worked with them.

Thinking is good, one thing Norm I have not heard you talk about.  Manufacturability, I can almost guarantee a lot of these holes are tooling points for the die when they are stamped and from a tooling point is easier to duplicate/mirror the holes than it is to not put them there.   Some of those holes were used for many things Dodge never decided to add to the truck or to change mid model and not have to change any tooling.  Also the holes could be tooling points while the frame is being put together.

 I doubt, almost guarantee with the analysis back in the 70's and 80's  they could not tell for sure where the stresses were in the frame to the degree you are talking about, also you are dealing with assembly line, union labor DONT think about your job and just get this thing together mentality.  Also Dodge never intended for the trucks to see the abuse and length of time in service.  Dodge for the most part built a truck that should be able to loaded to its max payload and be driven for 100K mils and not fail, I said in theory.  You bring up good points though, one day if I have nothing better to do I will draw up a frame from the RC and run thru stress analysis and see how it dose.       

Hey Norm just to add and I think we covered this before but I will sum up my frame experiences.  My RC had 180K when I bought it and the frame was perfect but the cowls were cracked very badly.  This was a stock truck but it did have the Warn winch bumper. 

The 1992 donor was a tall frame .250 it was a standard cab long bed LE package with many miles 300K I am guessing(ODO quit).  It had a goose neck and a big rear bumper and bigger rear hitch, the guy I bought it from pulled a Case 580 backhoe for over 200K every day.  The goose neck hitch was a homemade bolt in unit.
The rear frame was perfect, the front was cracked in the dimple area of the frame next to the steering box, but the steering brace was perfect.  The cowls were perfect.

Ok back to the RC, I repaired the cracks in the cowl area and I added crossover steering, I didn’t have any issues until I drove the truck to Alaska, after that trip I found two cracks in the frame, one right behind the crossover plate and the other in the area of the passenger side of the shock bracket mount.  I am not running big rubber.   So I pulled the front clip and engine out boxed the frame and beefed up the crossover area but, the cowl area was cracked again so I cut out all the fatigued metal, replace it with fresh steel and tied in the cowl area into the cab, I have not had it off road to really flex the frame so I don’t know how it will do, I am planning a trip in a couple weeks and I will inspect after that trip.

I agree with what you said about putting a big heavy thick bumper in the front of the Dodges if you do hit something hard you will end up bending the frame.     

longer rear springs and shackle flip...any suggestions??

Is there a reason you want to run a different setup in the back?

Another opinion question:

Stock grill or a home made one like this one on War wagon:

If you never intend on working on your truck then you can go the war wagon route.  I would run the stock grill and make a bumper to protect the front of the truck.  the War wagon unit looks cool but the first time you run into something (it will happen) you will not be a happy camper, the fenders, radiator, intercooler, AC system will take the brunt of the hit  (deer, Elk, Moose, rock that runs out in front of you).  keep it simple so you can work on the truck and protect the systems to keep you moving. this is just IMO!

Quote from: wilsonphil on April 10, 2015, 12:24:49 PM

Don the farm I grew up on we had this exact same base model, the engine and hydraulics are very dependable.  We had to rebuild the tracks and it was quite the job.  Parts were easy to get 30yrs ago but case is pretty good about supporting equipment.  Should be a fun project.

Great! We have a sorta SME on board here with us! I might be leaning on ya some via the PM route

Well good news is the undercarriage is solid, maybe 90%, so I wou't be able to wear that out.

We think everything on this old chunk has been rebuilt or replaced at least once. Since it's showing 5,000 + hours, my money says it actually has 15,000 hours. But there is a chance it is a 5K machine. If it is a 5K machine, then it has a lot of life left
If it is a 15K machine, then everything had to have been rebuilt at least once.

Take a look at the tracks. Grouser height is very good, and pins are hardly worn at all

Yes they look really good, its was a small fortune even 30yrs ago to rebuild the tracks that's why we did it ourselves.  We made up a press fixture and used a porta-power to press the bushings in.  If I remember correctly we used  a 15lb sledge to drive the pins out and then used the porta power to put everything back together.  It took some trial and error but the first track took a week and the other side we did in a weekend.  Also all that steel is case hardened, really like how you welded the frame 100% correct!!!     

  After I left for the Military my dad stopped farming and that was one of the pieces of equipment that my dad sold off, seeing pictures of it really brings back some memories. 

Ill send you a PM.

Next up is the stock right fender repair

I pulled the old rear anti lock brake computer out. It will not be reused

That is not RWAL computer!  Wish you were closer I could of given you a nice set of fenders for your project, nice thing about out west is the sheetmetal is not worth anything.

Well I have the truck back together running a driving.  It took about 30 min but the problem with the power steering was just air in the system, I just had to keep cycling back and fourth very slowly lots of air but I wonder if the pump is starting to give up the ghost its something I will keep an eye on.  Also I had to dremmel out the clocking splines on my pitman arm to make everything line up real nice.  Anyway all is good with the steering. 

  A shot  while I had it out today. The plan will be after I get some miles on the truck I will drop the cross member and modify it to give me enough clearance for the drive shaft. 

What I found out is anything is possible.  I will put the old box back on and see what happens, if I get the same problem then the pump might of died. I am trying to do this methodically and not throw pats at it.  it seems it always a crap shoot with rebuilt parts anymore.

Quick update, I have everything back together and have found a couple problems with the upgrades I just installed,

Problem one, I bought a Borgsen steering box back in October and just installed it while I put everything back together.  I drained the pump and hooked everything back up and filled with fresh fluid. I started the truck and cycled everything back in forth, shut down and topped off the fluid.  I then went and took the RC around the block and that’s when the fun started, all the fluid started foaming out of the reservoir.   The only thing I changed was the steering box and yes I have it plumbed correctly so I don’t know what is causing the problem.  I called Borgsen this morning and they told me to send the box back and they will test it, there is a three year warranty but I have to pay shipping.  Also I found out that Borgeson dose not build/rebuild steering boxes anymore I wonder why??? For now I will just throw my old box back on, it worked but had some slop after 200K miles.

  Second discovery,  When I rebuilt the NP205 I converted it to twin stick and I used a set of Off Road design NEW shift rails.  Well it seems that OFD did not cut the reliefs correctly and now my 4WD light is on even when the TC is in 2wd.  So I call OFD and they said that’s just the way it is and I don’t have a 4WD light now.  Its not a big deal and the TC performs as required this is just a FYI for anybody that dose the same upgrade.

I will upload pictures later.

Well that not a terrible price,  thats about what the other spring makers charge.  If you factor in shipping from any place that is not local to you the price will go up $100 for shipping.  $100 for a rearch is reasonable

When I started the RC project and started asking about springs nobody had anything bad to say about them, but lesson learned.  I have been to both Deaver and Atlas's shops(both in Southern California) and both are very knowledgable and great people to work with I have bought stuff from both.   

Ok making progress, engine and driveline is back in. just cleaning up the wiring and connecting all the plumbing.  If all goes well I should have it back on the road next weekend.  A few pictures of the progress, one problem I will address is the front DS is touching the cross member when the axle is fully extended the last picture shows the line around the DS, not a huge problem I just nee to drop the cross member and "cup" that area.

  What I have seen is the "off the self" springs are ok for the most part but they are massed produced and most of the springs are made in India or China, not all but most so please ask where they are made when you are going to buy them.

Ok I am NOT flaming or promoting any vendor with the story below, I am just explaining the lessons/experience I learned

  I have went thru 2 sets of rear springs and I am going to change the front springs also, just because I am very happy with how the rears are working.  I had bought new springs for the rear and the front from Alcan, and I learned a lot over the process.  I never had a problem with the Alcan springs I used BUT getting any information from Alcan is like pulling teeth for the most part.  When I ordered springs my goal was to get rid of the lift blocks, I hate lift blocks so with that goal in mind I went about of trying to figure out what kind of lift spring I needed.  After some back and fourth with Alcan I ordered what I thought would work and give me 4" total lift.  I learned you need to very clear when ordering springs!!!!  This is the first time I ever ordered custom a leaf springs so I really didn't know what to ask for.

 Anyway back to my first set of springs, so I installed the first set and a big problem I discovered was if you go over a certain lift/arch your spring will interfere with the rear stock spring hanger, for my application the interference wasn't there at first but over time the spring sagged/settled and the interference became a problem, more on this later.

 The first set of front springs I got had way to much lift, so I had to ship those back to Alcan and they replaced top leaf and then I was good to go the RC sat level and I was happy with every thing.  It was a harsh ride but it worked for what I was using it for.

  After a year of driving the RC I noticed the rear springs started to sag the spring was eating into the rear hanger and the spring bolt was hitting the hanger and limiting flex so much it was trying to rip the rear hanger off the frame, so I was getting ready to go to Alaska and I wanted to repair the problem before I went, I installed a set of Jims shackle flip rear spring hangers and then I called Alcan to order a new set of springs.  I wanted to soften the ride so I asked if they could give me a better fit/rate and I was told that I should just run a 1/2 ton pickup spring, I said ok but please make sure the dimensions are the same as my current spring.  I was skeptical but I agreed and the new plan, well when the springs came in I knew right away they were not going to work.  After I installed I found that the spring pin was 1" father forward than the last spring they built for me and the springs were way too soft.  so I installed a set of zero rates to fix the axle position problem and I still had to install a 2.5" lift block to get the RC to kind of sit level, basically the springs were flat with weight on them and only I loaded everything up the springs were negative.  At this point I was out of time and just had to make the trip with what I had, we made the trip without problems.

  Once I returned from Alaska I took the RC to Deaver spring, he took measurements and in about 3 weeks later the springs were built, total difference now that the RC has proper springs, its about 1" higher than I want but Deaver said if I wasn't happy to bring the RC back and they would make it set where I wanted it.  I am so happy with what they did with the rear I am going to have them make a set for the front.

  As you can see I went thru a lot to finally get what I wanted but I learned a lot about leaf springs, there is a total different approach in how Deaver builds a spring than in how Alcan builds a spring, they with both work but they  are engineered differently.     

  This ended up being a expensive lesson but I am glad I know what I know now.

Helping Hijack, Don where did you end up getting your springs?  I have really learned my lesson on leaf springs.  Basically I learned that “Store Bought” springs suck and custom springs are good but the person making them has to understand what the spring is doing.

When I bought my 06 Dodge I was driving halfway across the US pulling a car trailer every couple months and I wanted/needed a dependable truck.  My 06 has given me zero problems and never stranded me and has been the most dependable truck I have ever owned but its 100% bone stock and I take very good care of it, pulling a trailer I am lucky to get 14mpg @ 70-75 mph.  100% agree on the electronics side but that is a present from our lovely EPA.  In the event of the EMP I have the RC so I'm good to go there and I can carry about 50-55 gallons of fuel with the RC so hopefully that will get me out of harms way.

  I don't think my RC will get anywhere close to the fuel mileage to what my 06 Dodge gets , there is just to much frontal area and it is lifted too much and aerodynamics are terrible but I run 70-75 with the RC when I'm on the freeway and I like to be able to run that fast and not make the Cummins scream(I'm running 2000rpm) and get 15mpg.  I am running the 3.54 gears and 31" tire and I don't have a lockup TC so I know that will hurt me on MPG.  The Cummins in my RC came with a 14cm wastegated turbo, and I have done the "normal" adjustments so I am running 28psi boost and EGT never go over 1150F @ the manifold.  Right now I can pull into NAPA and get almost any part I need to get back on the road but the axles, transfer cases, transmissions are starting to get pricey even for a core.

  What I am seeing happen now is even a worn out 300K Cummins truck is going in the 7.5K to 12K price range and then you almost have to rebuild everything BUT the Cummins.  The price of the project starts to go up very fast and that is why next truck will be a late model running gear  with a RC body and 12v Cummins P-pumped.
 

Well I'm glad someone likes the project!!

I've been lurking over here for awhile but I hope I can pass some of my lessons learned to someone else on their projects.

Hello Everyone,

I just wanted to post a link up here of the Ramcharger build I have been working on, its a 1990 that I converted to Cummins power and W250 driveline.  I am always making improvements and I will post those here also.

http://ramchargercentral.com/diesel-talk/hello-everyone-my-soon-to-be-ctd-ramcharger/

when you have nothing better to do take a look at the link and learn how not to make some of the mistakes I made!!!

Great build, doing something very similar to my 1990 Ramcharger.  Since it was pouring rain Sunday I spent the day reading thru your build.  I don't know if you are still looking for them but Quad4x4 sells the rotor dust shields for the Dodge D60, they are very pricey so don't be too shocked!!  Keep up the great work.