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6.5 Grendel HUGE bullet runout. NEED HELP.

So do you have a match chamber in the Grendel AR? If not, it probably won’t matter that much, especially if you are loading from the magazine. The main question is have you shot those loads to see how they perform?
You may be obsessing over a detail that isn’t important for the platform you are shooting.
Yes I have shot them prior to knowing what the runout was and they did ot beat or match or even get close to being as accurate as the 123gr Hornady ELDM factory ammo. The factory stuff has far less runout than I have. It's very frustrating to me to see my runout that poor. Either its something to do with the process or equipment related to the Grendel reloading. My 308 is making good ammo. Their is something going on that I need to figure out because, it could give me issues on other ammo I reload in the future. Would really stink to get a F class rifle and feed junk ammo to it. There has to be something I am missing or doing wrong.
 
I am thinking about getting some Berger bullets since they are supposed to be as good as any for match. I have concidered maybe bullets are total crap for seating. I don't have this issue with the 308. So something is different.
Then the 6.5 Grendel dies are more then likely the culprits, be it the resizing die or seating die.

Also. If you’re considering trying Berger bullets, here is their tch help contact phone number;
660-460-2802.
A member on this forum just last week gave me the phone number as the tech help can answer questions about Lapua products.
 
Brass usually dents case necks in, it doesnt screw up consentricity.
Just going by what I have experienced. All brass gets deprimed then wet cleaned and annealed on AMP then is sized the same way by using a full length die with no expander followed by expanding using a mandrel. Bolt gun brass concentricity is consistently .002 or less. Brass that has been cycled through one of my gas guns gets up to .005 or greater. I quit worrying about it, all my AR's shoot consistently below 1 MOA, in NRA sanctioned AR competitions that is the equivalent of .5 for a bolt rifle
 
I am starting to think about that. I have checked new Lapua brass and it's pretty good. Not too much to do in order to eliminate dies and such. I will first check my bushing for concentricity. It's entirely possible the bushing is not any good. Then I will start my process and after each step check for changes in the shell case to see if it reads differently. I will have areas marked on the case for measurement locations so I can verify that proximity is still round. Maybe I can narrow it down that way. As it stands it won't hurt to try.
 
Then the 6.5 Grendel dies are more then likely the culprits, be it the resizing die or seating die.

Also. If you’re considering trying Berger bullets, here is their tch help contact phone number;
660-460-2802.
A member on this forum just last week gave me the phone number as the tech help can answer questions about Lapua products.
Thanks for the contact. I have found very quickly that Berger 6.5 bullets are unobtanium right now. Certainly nothing in the 120gr-130gr bullets nor any of the others to be honest. Is there another bullet maker that is top notch and used by top shooters?
 
Just going by what I have experienced. All brass gets deprimed then wet cleaned and annealed on AMP then is sized the same way by using a full length die with no expander followed by expanding using a mandrel. Bolt gun brass concentricity is consistently .002 or less. Brass that has been cycled through one of my gas guns gets up to .005 or greater. I quit worrying about it, all my AR's shoot consistently below 1 MOA, in NRA sanctioned AR competitions that is the equivalent of .5 for a bolt rifle
I wouldn't worry about it so much if my dies and such weren't doing the same thing to my new Lapua brass as it does with my previously fired Hornady brass. That's what I am having issues with. I get dented necks on my Grendel brass as well. I definitely have taken that into consideration. It's just that the stuff is so far off after trying to get it right.
 
A couple of thought based on AR15:

1) Turning Necks - I would be hesitant to do any neck turning for an AR15 chamber, which are usually intentionally loose. Unless you have a match chamber or have confirm chamber’s neck, your chamber is most likely generous compared to a bolt rifle. If you feel the need to neck turn then maybe only lightest of skim cut.
2) Neck Tension - .001”-.002” is fine for bolt rifle, but most likely will be insufficient in AR15 (unless you are also crimping). If feeding from magazine then guidance is .003”-.004” of neck tension for AR15. You can always test your neck tension to see if bullets shift (COAL) is changing (shortening or elongating) as result of BCG slamming closed. This may effect the cartridge being chambered as well as any cartridges stacked in the magazine.

just a couple of thoughts right off.
 
I wouldn't worry about it so much if my dies and such weren't doing the same thing to my new Lapua brass as it does with my previously fired Hornady brass.
You do realize that FL dies are cut with a 1 piece reamer don't you? There is no way that the neck portion and the body portion of a FL non bushing die can be non concentric

edited for better pic of reamer
 
Last edited:
I use a good bit of Lapua 6.5 Grendel brass that I neck down to 6mm. IME, runout is usually traceable to something in the sizing operation. It can be as simple as the lube but is typically due to moving the brass too much during sizing. My fired brass runs out very good opposed to my necked down virgin brass, for example. You said that you are necking it down then expanding back up. I'm gonna say that this is where you'll find your problem. Try a bushing that is .002 smaller than your loaded round and without expanding it back up.
 
I use a good bit of Lapua 6.5 Grendel brass that I neck down to 6mm. IME, runout is usually traceable to something in the sizing operation. It can be as simple as the lube but is typically due to moving the brass too much during sizing. My fired brass runs out very good opposed to my necked down virgin brass, for example. You said that you are necking it down then expanding back up. I'm gonna say that this is where you'll find your problem. Try a bushing that is .002 smaller than your loaded round and without expanding it back up.
just out of curiosity are you firing that brass in bolt or gas operated rifles? My bolt .308 and AR .308 are sized on the same dies using the exact same process yet the runout on the AR 10 fired is double what I get on the bolt rifle brass.
 
Oso pretty much summed up what I was going to say next. I would wager that the difference in accuracy between factory ammo and your hand loads has nothing to do with runout and everything to do with the fact that you are feeding an AR bolt gun match ammo.

The cycling process in an AR is hard on ammo. If you don’t have good neck tension or a good crimp, it doesn’t matter what your runout is when you are done loading it, because it damn sure won’t be that once it is cycled into the chamber during firing. Also, it is very difficult to match factory ammo with hand loads. Chances are if you quit chasing runout, put a bit more neck tension in (or a crimp) and experiment with powders and charges, you will find the right mix that meets or beats the factory Hornady loads.
 
You do realize that FL dies are cut with a 1 piece reamer don't you? There is no way that the neck portion and the body portion of a FL non bushing die can be non concentric

edited for better pic of reamer
I realized that. The only things I think of that would offer concentricity issues would be the expander on the decapping pin (not using) and bushing being out of conformity (pulled, cleaned and verified that it can float) . That's why I am leaning towards bullet neck tension or seating die. But since I have used a Wilson chamber die to check my Forster die and getting close to the same results, I am starting to lean towards neck tension or the bullet. I just go done going thru my process and measuring the case at every step I can't help but think that something is wrong with the bullet or tension. Neck diameter before seating is at 0.2625 and neck walls measure at 0.0135 up until seating neck conformity (without turning) is between 0.0005 and 0.0015. This is where I am confused. I can't understand why I am getting the bullet runout I am.
 
Oso pretty much summed up what I was going to say next. I would wager that the difference in accuracy between factory ammo and your hand loads has nothing to do with runout and everything to do with the fact that you are feeding an AR bolt gun match ammo.

The cycling process in an AR is hard on ammo. If you don’t have good neck tension or a good crimp, it doesn’t matter what your runout is when you are done loading it, because it damn sure won’t be that once it is cycled into the chamber during firing. Also, it is very difficult to match factory ammo with hand loads. Chances are if you quit chasing runout, put a bit more neck tension in (or a crimp) and experiment with powders and charges, you will find the right mix that meets or beats the factory Hornady loads.
But I am getting the same runout problem with unfired loaded Lapua brass. That eliminates the fact that the Hornady brass has been fired. Results on both new and old brass are identical. So that validates an issue with dies, bullets or process. But my case measurements are good until seating
just out of curiosity are you firing that brass in bolt or gas operated rifles? My bolt .308 and AR .308 are sized on the same dies using the exact same process yet the runout on the AR 10 fired is double what I get on the bolt rifle brass.
Never fired Lapua through the AR only Hornady brass. However, getting nearly identical bullet runout with both set of brass. Got me scratching my head bad trying to figure out why the bullets are tipping over and getting runout on seating operation. Not having this issue with my brass for my M1A 308 loads. Rounds are concentric for it never fired and old brass. I am wondering too if the boat tail on the 123 eld is not conducive to good seating and needs to be a bit longer for the bullet to get far enough to self align with the case.
 
What was the runout on the case you just measured?
New Lapua bare case unsized is
0.001 at neck
0.001 just behind shoulder
0.0005 at middle and back of case by rim

After resize (just for giggles)
0.002 at neck
0.001 behind shoulder
0.0003-0.0005 at middle and back

After seating bullet runout
0.009 near tip
0.0055 at near back of ogive.
 
Something is wrong with the dimensions you gave above. You say neck walls are .0135" that equals .027", add that to .264" bullet diameter and you have a loaded bullet diameter of .291". You say neck diameter of case before seating is .2625". I hope that's inside diameter and not outside diameter. Also you say on original post that you size the case and with the Century mandrel you have .0015" of neck tension. So you run the mandrel after sizing? I'd say the mandrel is not centered in the die giving you the runout. Check brass runout after sizing and then check again after running mandrel. I see your new post. Looks like brass is fine after sizing.
 
I use a good bit of Lapua 6.5 Grendel brass that I neck down to 6mm. IME, runout is usually traceable to something in the sizing operation. It can be as simple as the lube but is typically due to moving the brass too much during sizing. My fired brass runs out very good opposed to my necked down virgin brass, for example. You said that you are necking it down then expanding back up. I'm gonna say that this is where you'll find your problem. Try a bushing that is .002 smaller than your loaded round and without expanding it back up.
My bushing is 0.285 sizes interior down to 0.255
I use a good bit of Lapua 6.5 Grendel brass that I neck down to 6mm. IME, runout is usually traceable to something in the sizing operation. It can be as simple as the lube but is typically due to moving the brass too much during sizing. My fired brass runs out very good opposed to my necked down virgin brass, for example. You said that you are necking it down then expanding back up. I'm gonna say that this is where you'll find your problem. Try a bushing that is .002 smaller than your loaded round and without expanding it back up.
I will have to give that a try. I will also have to order it. Right now my 0.285 bushing brings the interior neck dimension to 0.2565. If I run my mandrel it comes back up to 0.2625. I will order a couple of bushings just to give me some room to play with.
 

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