MEC 's new Single stage Press

[survivalshop]

Because of a Vet appointment ( f'ing dogs ), I have to put off range time till tomorrow , damn it ! 

[survivalshop]

    Not a good day , had all kinds of issues with not being able to chamber cartridges , seems like its a shoulder set back issue , can't get enough set back , had the Sizing die base as far as it would go , touching the Shell holder . Maybe I'm over sizing them with this new press , not sure , never had this issue be fore , only time I had an issue with chambering , was when I first started to reload for the .223 & over crimped them & set the case shoulder back with a bulge . That was forty years ago , I have heard & read before that some have had to trim a Shell holder down to get proper set back , wonder if I have to do that for this new Press .

     I have LE Wilson Case gages ordered , so I have to do some inspecting , because all my reloads from the Pacific Press worked fine , the reloaded ammo from the MEC would not chamber in my 308 Bolt gun I took with me to sight in for the first time , could not close the Bolt . Its not COL , because I had various COL's to test & none would work , had to use a screw driver to pry the BCG back one one to get it out of the chamber .

    Its funny , because I always test a loaded round to make sure it Chambers & ejects before I continue with Bullet seating , Even a sized case is tested before I continue Sizing , so something is amiss , just have to figure WTF is going on . 

 Rifle shot good when she shot , 10 shot groups made on big hole , but with the issues , I couldn't get going enough to compare anything , too much BS .

Edited March 1, 2017 by survivalshop

[survivalshop]

  Well found out it is Shoulder set back (case HS ) , here's what I did , I took some of the Brass that was sized with the MEC Press & the Redding Bushing Die , made sure the Bushing was set correctly & it was , lubed a case up , resized it in the MEC , just to make sure I didn't mess up somewhere , cleaned the Lube off with 70% Alcohol & fed the empty case in the 308 Bolt action & it wouldn't let the Bolt seat , got my old RCBS Small Base Sizing Die out & set it up , resized the same case & trimmed it , & it too would not let the Bolt close .

 I then put the same Shell Holder in the Pacific Press , adj. a little cam over on the Linkage of the press with the same SB Sizer Die & sized it , and it had no problem closing the bolt on the 308 Bolt action . Then I took another different case from the Brass sized on the MEC & changed Sizer Die's to the Redding Bushing die , set it the same as the RCBS SB Sizer die & sized the case & it too had no issues closing the Bolt !

  I'm going to contact the Engineers for MEC to see what they have to say about this new issue , which is not all that odd , as said above , I know some & read of others who had to cut down Shell holders to get the proper Shoulder set back . I'm just wondering if they sell their own & I may have to look at their web sight to see .

[survivalshop]

  Damn , emailed the Engineer's at MEC last night & they called me this morning to see how they could help . Damn !    We talked about it & he sent me an article to read that might help & he also said he has heard or other reloaders with other press's that have had that issue & that turning down the Die or Lapping the top of the Shell Holder are the cure. I prefer to lap the SH myself , its the less expensive of the two & I can use it for other calibers I reload for . Just waiting for my Gages to see how much to lap off .

[sketch]

 SS are you sure they arnt just using you to help build/develop a better press??  Good cs ?

[MikedaddyH]

SS send MEC an invoiced bill for several hundred dollars and label it R&D . Charge them with time ,equipment that you had to purchase because their equipment was out-of-spec and brass that was used... That will get their attention !

[survivalshop]

  Lapped 0.0155" from the face of the Shell holder & Cases chamber with out an issue . I did five in a row & all chambered in the Bolt Gun.

     I know your asking  , how I determined how much to take off , well I took my digital Calipers & measured the shoulder to the Base of a known feeding case , I know its not precise , but it was good enough to get an idea on what should be taken off .  I measured all four of my 308 Shell Holders , 2-RCBS & 2- Lee's , I measured the depth from the face of the Shell Holder ( top ) to where the Base of the Cartridge sits . The lowest I got was from the brand new never used , RCBS , reading was 0.1305" , all others were very close , but wanted to start as low as I could , less to take off .

    I started by lapping on my Marble lapping platform with  600 Aluminum Oxide & it just wasn't going fast enough , so I had a spare Grinding wheel for my Bench Grinder & laid it down & lapped the face or top of the Shell holder till I got a few Thousands off & tried to resize a case until I got it to a point where I could close the Bolt , but it was kinda stiff , then I went back to the Aluminum Oxide till I got the Case to feed nicely , then lubed , sized a few cases to make sure it was not a fluke .

 When my Case Gages arrive , I will get a much better Idea on where they are at & make adj. as necessary , even if I need to start with another Shell Holder .

Edited March 2, 2017 by survivalshop

[survivalshop]

 Here is an article  http://www.accurateshooter.com/technical-articles/die-issues-when-bumping-shoulders/ That he sent me , which I had already read yesterday , but this could be an issue also . I Have two other presses that use this Die with out issue , though I agree now , a Case Gage is an important tool & I have been reloading for about forty years & have never needed one , but now after this episode ,I will have one for every caliber I load for , just to make sure .

 Maybe I've been lucky all these years , but I think sound reloading practices has got me to this point > I just wonder why my test loaded round & my Dummy round I made , just before it , fed with out issue in the 308AR before I went to the range yesterday.

[survivalshop]

 I found another older RCBS Shell Holder today & it was 0.009" less then all the unaltered ones & as far as chambering the ones I tested , they chamber fine & the Bolt closes on the Bolt gun normally . My Gages should be here Saturday , so I can see where this ammo stands , but it looks like Tolerance Stacking even on a reloading press , I have four RCBS & two Lee Shell Holders that all have different tolerances , interesting .

 I also found an odd measurement that I believe may not have anything to do with the issue . I took a depth measurement from the very top of the Ram ( with out the Shell Holder ) to the inside shelf in the Ram that should or shouldn't make contact with the bottom of the Shell Holder .

 MEC ---  0.265"

Pacific -- 0.250" 

 I don't see how that difference can make any difference , because the Shell Holder contacts the Base of the Sizing Die , so it has to be something with the Shell Holder or like that article read , the Die . Then again, those Dies have worked with two other completely different types of Presses & never had an issue .

[survivalshop]

  I pulled about 70 Bullets & dumped the charges back into the Powder container today . Don't trust any of the Ammo made by the MEC before I found the Shoulder set back issue  &this Shell Holder that works , but don't really know until my Gages show up tomorrow . Might not have had to pull them all , but better safe then sorry .

 I will be checking all sized brass from now on .

 

Edited March 4, 2017 by survivalshop

[survivalshop]

      Gages came today & everyone of the Sized Cases from the MEC Press, Redding Die with my normal RCBS Shell Holder, are over the Max Head Space . All the ones with the same Die & Shell holder Sized in the Pacific Press are right at the Min. HS . 

    The instructions read to take a fired case & check where it sits in the Gage & it should be just below the bottom face of the gage ( Adj. Die up or down to achieve it ), the slot cut below that bottom face is the min. HS for the case. Case should not go below this point .

     So Looking at the cases sized on the MEC with the Shell holder that I found that sets the Shoulder back for them to work for Chambering , is set too deep , I need to Back the off or unscrew it to change the set back on the Shoulder, just a little .

 This is one  below thats beyond the Max. & its just enough to keep the Case from Chambering , I will measure one tomorrow , but its not much .

 Now I can recharge & seat those seventy odd Bullets I pulled yesterday 

[MikedaddyH]

SS you have way more patience than I do. I would have given up on the MEC press and had a Dillion mounted on my bench by now. Instead you have more cool gauges and measurement tools in your possession.

[survivalshop]

 I already have a Dillon 550B on the bench 

  I have figured it out & its part my fault for not completely being familiar with the new Press for the cases not having the proper Shoulder set back .Here's what I found ,

      When I first set up the MEC Press ,I found that because of the straight link to the Ram with the Press's Handle , there was no ability to Cam over the Linkage a little to take any play out when the Shell Holder contacts the Bottom of the Sizing Die . I set it up to contact the Shell Holder with the Sizing Die & since I use the Desk top for a stop , I made sure there was a slight gap so that I could take out any play even though there was no way to cam over . I still would contact the Press's Handle to the edge of the Desk top with a slight force , so I know I was consistent in every stroke . This is where I was not setting it up correctly , because I found that with a Unsized case , there is some play in the Linkage system , even though I was hitting the edge of the Desk & it being my stop gage , it was not enough .

      With this MEC Press & probably more because of the once fired Surplus LC Brass , probably shot out of an Belt fed & needed a good deal of force to get the proper Shoulder Set Back . With the Pacific , I alway set up a slight Cam over when the Shell Holder made Contact with the Sizing Die , so it wasn't an issue , I still used the Desk top as a stop , but with Cam over ,so when sizing a case , it forced the case deeper into the Sizing Die.

      The MEC , I don't use the Desk top as a stop , I just size until the Press Ram stops , I probably could still use the desk as a stop , but now I use the , go as fas as I can , stop & its working , I can feel the Shoulder setting Back now , so there has to be a little play in this direct linkage , super very little , but still some play .

      I took a measurement , roughly , on how much the Base of the Case is past the Max Case HS , its roughly 0.0011" ,( I think I typed that right 11 thou. ) Like I said its not very much . I have also found that both press's with the RCBS Shell Holders are putting the Case HS , right at the Min. on the Gage. Knowing that all the the Shell holders I have ( for 308 ) all have different measurements as far as thickness or the Shell Holder & depth of the where the Case Base sits , they are all very slight , but they are different . I found that all the RCBS give me Min. Case HS , so I tried my one of my Lee Shell Holders & it brings the Case HS right where it should be , between the the Min & Max . 

  All this Brass I'm using is Once fired Milspec LC surplus , now after its fired in my Chamber , I may be able to make adj. of the Die to be able to use the RCBS Shell Holders , but will not know that until I Anneal the Brass I fired the other day at the range to know for sure & will post those results also . 

     Everything I have ever read gives instructions that you can adj. the Sizing Die to get the Proper Shoulder Set Back , now that I have gages for every Bottle Neck Caliber I load for ( except for 300BLK , it was out of stock at the time I ordered  ) , I will see if If this is possible with the Dies that I have , because I have never had a Gage to go by . but looks like for this 308Redding Sizing Die , I have no adj. except for the Shell holders & I now have one that is 0.0015' shorter then the rest , so I can use it , if need be , to get the adj. I need , at least for the 308 class of calibers that use this Shell Holder .

   

[MikedaddyH]

I have only had one problem with shoulder spacing , it was with .357sig cases. I was making .357sig from .40s&w 1X cases and had to take .011" off of the rcbs shell holder . The rcbs die set work perfectly on the case after the adjustment,

[survivalshop]

10 hours ago, MikedaddyH said:

I have only had one problem with shoulder spacing , it was with .357sig cases. I was making .357sig from .40s&w 1X cases and had to take .011" off of the rcbs shell holder . The rcbs die set work perfectly on the case after the adjustment,

  I have always read about other reloaders having to do it , but never need it myself , well , until now .  

 I reloaded that 70 some rounds & made a new Dummy round with a COL of 2.775" for the 155 gr. SMK & it had no issues with any of the 308AR's or the Bolt Gun , so now that I learned how to reload again , I think this Fodder is ready for another testing . I reloaded the same brass or what was left , that still had the way out , run out , a couple have over 0.0010" & all so far that are Made on the new MEC is all below 0.002" run out . Going back to the range Tuesday , with all the other old farts again .

[survivalshop]

 I have to admit , the combo of Press & Dies , sure make some precise Ammo , Out of fifty , only five were over 0.001" run out & they were between 0.002" -0.004" . I have never had a Concentricity Gage before , but measuring a vast amount of my reloads & Factory ammo , most are in the 0.004" or slightly above run out , this is just amazing to me . 

 Now the trick is , will these dead nuts ammo out shoot various , out of normal or normal run out ammo , thats the real question ,but they may not show off at shorter ranges , I think , longer range they may have a better showing & I think I found a new 600 yard range close to me 

Edited March 7, 2017 by survivalshop