Reloading For An AR-10 In 6.5mm Creedmoor LMT MWS

[Fire4Effect]

I have the following components I would like to use to load for my LMT MWS with a 20” 6.5mm Creedmoor barrel. The LMT MWS is stock except for a BRT EZTUNE gas tube.

• Hornady 6.5mm 140 gr EDL Match bullets with Hodgdon H4350.
• Hornady 6.5mm 147 gr EDL Match bullets with Hodgdon H4350.

https://www.snipershide.com/shooting/threads/lmt-mws-brt-eztune-gas-tube.7032995/

All of the published reloading data for the Hornady 6.5mm 140 gr EDL Match bullets with Hodgdon H4350 powder were tested in bolt action rifles.

• Hornady Reloading Data: Max load 41.5 gr.
• Hodgdon Reloading Data: Max load 40.0 gr.

All of the published reloading data for the Hornady 6.5mm 147 gr EDL Match bullets with Hodgdon H4350 powder were tested in bolt action rifles.

• Hornady Reloading Data: Max load 40.3 gr.
• Hodgdon Reloading Data: Max load 41.8 gr.

I am assuming these numbers are safe in bolt guns, but not in the AR10 platform.

Can anyone recommend a good starting point and not to hot max for these components in an AR-10?

Thanks

 

[ZenArchery]

As with all reloading start below max and work up. Your shooting system will tell you when to stop. My gas 6.5 CM is above data you listed but that’s my gun.

 

[Fire4Effect]

As with all reloading start below max and work up. Your shooting system will tell you when to stop. My gas 6.5 CM is above data you listed but that’s my gun.

Unfortunately all the data is for bolt guns. Are you using the powder and bullet combinations I listed above?

 

[Old Navy]

41.4 of H4350 was perfectly safe in my Aero with all the 140 class bullets. The 140 VLD was my favorite.

 

[Pawnee Bill]

Do you have an adjustable gas block on your rifle? It is a necessity for load development and makes it easier on brass.

 

[Fire4Effect]

Do you have an adjustable gas block on your rifle? It is a necessity for load development and makes it easier on brass.

No one makes an adjustable gas block for the LMT MWS. I did install a BRT EZTUNE gas tube that reduced the overgassing dramatically.

https://www.snipershide.com/shooting/threads/lmt-mws-brt-eztune-gas-tube.7032995/

 

[Fire4Effect]

41.4 of H4350 was perfectly safe in my Aero with all the 140 class bullets. The 140 VLD was my favorite.

For the 140 gr EDL Match I think I will try the following ladder:
40.3
40.6
40.9
41.2
41.5 (Max load according to Hornady)

Hodgdon states 40.00 gr is a max load. Can this be correct?

Brass: Once fired Hornady.
Primer: Winchester WLR
Or
Brass: New Lapua small primer
Primer: CCI Small primer magnum #450.

What is the overall cartridge length recommendation. The Max is 2.825” which just kisses the front of my magazines.

 

[6ShotsOr5?]

The only 6.5 Creedmoor I have is an AR-10 but I haven’t reloaded for it. I assembled the rifle from a mixed bag Mega receiver group, Rainier 22” barrel with rifle+2 gas system, etc. I always shot it suppressed and the adjustable gas block was a big help in making the rifle reliable. I have some MV data on the factory loads with your chosen bullets in this rifle if that would help.

 

[Fire4Effect]

The only 6.5 Creedmoor I have is an AR-10 but I haven’t reloaded for it. I assembled the rifle from a mixed bag Mega receiver group, Rainier 22” barrel with rifle+2 gas system, etc. I always shot it suppressed and the adjustable gas block was a big help in making the rifle reliable. I have some MV data on the factory loads with your chosen bullets in this rifle if that would help.

Thanks, but I am looking for reloadng data. My LMT MWS shoots factory ammo without a problem.

https://www.snipershide.com/shooting/threads/lmt-mws-brt-eztune-gas-tube.7032995/

 

[Coyotefurharvester]

If it shoots factory ammo well and you have a chronograph. Work up a load that is very close in velocity. Factory 2700 fps with the 143. Hodgdon data has bunch in that range.

 

[Fire4Effect]

If it shoots factory ammo well and you have a chronograph. Work up a load that is very close in velocity. Factory 2700 fps with the 143. Hodgdon data has bunch in that range.

I have a chronograph. What concerns me is that Hodgdon lists the max load of H4350 as 40 gr and Hornady lists it as 41.5. I plan to start above Hodgdon’s max but well be low Hornaday’s. Are these numbers correct? It sounds like many are loading closer to Hornady’s max.

 

[Fire4Effect]

This is what I plan to do.

I have the following Hornady factory ammo:

Hornady 6.5 Creedmoor 140 gr EDL Match
Hornady 6.5 Creedmoor 147 gr EDL Match
Hornady (American Gunner) 6.5 Creedmoor 140 gr BTHP

I have a chronograph and will fire 10 rounds each of the above through my LMT MWS to observe and record data. If all looks good I will try my 140 gr EDL Match handloads and work my way up the ladder until I see pressure signs. I will do the same for the 147 gr EDL Match handloads.

This is what I loaded yesterday with my available components:

*******************************************************************************************
For the 140 gr EDL Match I loaded the following with Hodgdon H4350:

40.3 gr
40.6 gr
40.9 gr
41.2 gr
41.5 gr (Max load according to Hornady)

Hodgdon states 40.00 gr is a max load. Can this be correct?

Brass: New Lapua small primer
Primer: CCI Small primer magnum #450.
COAL: 2.81”

*******************************************************************************************
For the 147 gr EDL Match I loaded the following:

40.0 gr
40.3 gr
40.6 gr
40.9 gr
41.2 gr

Hornady states 40.3 gr is the max load.

Hodgdon states 41.8 gr is a max load.

Brass: Once fired Hornady.
Primer: Winchester WLR
COAL: 2.81”

*******************************************************************************************

 

[ebb]

Go to JP rifles site and read his instructions on loading for his rifles in 260 rem. It was an eye opener for me, he seems to make excellent rifles, and knows what he is talking about.

 

[Fire4Effect]

Go to JP rifles site and read his instructions on loading for his rifles in 260 rem. It was an eye opener for me, he seems to make excellent rifles, and knows what he is talking about.

Thanks, I took a quick look. It does not address the combination I am using, but looks like useful information.

 

[markm87]

I'd back of a full grain and start from there. The LMTs are frickin BOMB proof. My gas gun load is the same as our bolt gun load, but I have the body die dialed a little lower to get the ammo to chamber.

When I've shot the MWS with a slightly reduced load and the silencer removed, it's a much more enjoyable experience.

I think we have the BRT reduced gas tubes in the LMT uppers because they are generously gassed to say the least.

 

[Fire4Effect]

I'd back of a full grain and start from there. The LMTs are frickin BOMB proof. My gas gun load is the same as our bolt gun load, but I have the body die dialed a little lower to get the ammo to chamber.

When I've shot the MWS with a slightly reduced load and the silencer removed, it's a much more enjoyable experience.

I think we have the BRT reduced gas tubes in the LMT uppers because they are generously gassed to say the least.

I did reduce at least 1 grain from the max loads. The LMT chambers in my .308 and 6.5CM barrels are generous and I do full length resize. My .308 20” barrel is very accurate and all my barrels have BRT reduced gas tubes.

 

[ebb]

JP doesn't like using anything over 130 grain if I remember correctly. Mine was so rough on brass when using 140 and a decent load that I gave up on the heavier bullets and like the 123 grain.

 

[Fire4Effect]

JP doesn't like using anything over 130 grain if I remember correctly. Mine was so rough on brass when using 140 and a decent load that I gave up on the heavier bullets and like the 123 grain.

Adding a piece of Velcro to the ejection port deflector and the BRT gas tube helped a lot with factory 140 gr 6.5 Creedmoor ammo.

 

[danny]

Unfortunately all the data is for bolt guns. Are you using the powder and bullet combinations I listed above?

In my opinion, you are going about this the wrong way. You seem to have this "bolt gun" not bolt gun concern. That implies to me that you are concerned only about powder charge with a powder you have already selected, because you have it. That is backwards thinking. An AR 15 is essentially a bolt action of sorts until the gas system starts functioning. An AR should generally handle loads that average bolt actions can handle, and the charge can be limited by the signs your rifle shows you (someone already mentioned that). What you should be doing is selecting a powder based on suitability for an AR's gas system, your cartridge and the bullet you will use, then go from there.

Danny

 

[ebb]

Mine is a DPMS LR in 260 REM, but the damage to the cases was not due to the cases hitting the rifle on ejection. The extractor grooves were damaged . A friend with several of the same rifles as mine, in 243 WIN sent me to JPs page and after seeing how well the 123 or 130s worked I never looked back at the 140s. I don't know but I think it's a fire, extraction timing thing, I thought making the140s to work well could be solved, it just wasn't worth the time and energy. YMMV, good luck with it and keep us posted.