HELP Accuracy Howa 6.5 Grendel

[mrab88]

Hello Forum:

I have a Howa 6.5 Grendel in an Oryx Chassis (bought from factory). I recently put a YHM Resonator R2 on it (very quiet suppressor). The gun shoots Hornady American Gunner into .5 - .75 MOA groups. However, Hornady Black ELD-M prints larger than 2.5 + MOA. I cannot figure out why the Hornady Black won't print. This is a problem because American Gunner is nowhere to be found.

I cannot remember if my bolt rifle printed better groups with Black before I put on the suppressor. However, I have fired groups with the suppressor on and off (YHM muzzle device remained on) and found no different with the poor performance of ELD-M.

I'm open to suggestions if anyone has any idea what may be going on.

Thanks!

[mdram]

it just may not like it, not every gun shoots every round the same

[m796rider]

Some bullets don't like any jump to the lands -- this can be a bit of a problem with the Howa chamber having a fair amount of freebore. It may just be that the American Gunner bullets jump better than Black. I know Berger 130 Hybrids also have an issue with jump and you need to experiment with COAL to find the sweet spot...

[raamaudio]

I have a bunch of AG for sale and a bunch of ELD I was going to keep for my ARs which I am getting out of so now I better get my Howa out and shoot it to see which one is best as I might have to sell the ELD and keep at least most of the AG. Glad I saw this thread as just had not considered this, major oversight on my part.

[kmon]

Rifles can be beasts unto themselves. Some shoot some ammo much better than others and do not expect the same loadings to be the same across lot numbers they will be close but can be enough difference to notice with different lots of ammo.

Hornady Light Mag shot half inch groups at 100 yards in my 7mm-08 but their replacement Superformance shoots patterns not groups. The SF I tried from it were if lucky 6 inch groups at 100 yards but follow that group with Light mag or my favorite hand load back to half inch. I talked with a few people at Hornady and they said that is not surprising as 2 of them had experienced such with their personal rifles. Once the Light mags are gone it is back to reloads for me with that rifle, which I do not hunt with as much since I got the bot action Grendel.

Factory ammo is IMO a crap shoot, roll the dice on loads until you find one the gun likes and buy all you can of that lot number if you are a dedicated factory load shooter.

For the OP and what to do start searching for what your gun likes. Good luck

[Oso Polaris]

I think that it is a rifle specific issue/preference. With a good quality suppressor and rigid/thick barrel there is marginal POI.

My Howa Mini is the heavy barrel (20") in B&C stock with action bedded and shooting with a Thunderbeast. It will shoot Hornady Black Box 123gr ELD Match ammo in the 1/2" group size and at same time it will shoot as well or better my reloads with 123gr SST ll from a range of seating depths (0.008" jam to .005" jump) without any major difference.

I took some measurements on the Hornady ELD Match ammo, which had a CBTO of approx. 1.606" out of the box. Using a Hornady OAL Gage, my rifle to the lands for the ELD Match bullet has a CBTO of 1.664". That is almost a 0.060" jump in my rifle... my rifle didn't seem to care. Again, each rifle is its own beast

[mrab88]

So, it sounds like I am just unlucky that my barrel does not shoot ELD-M well. That is a shame as I have 200+ ELD-M but very little AG. I suppose I could reach out to Legacy Sports International. Alternatively, I could rebarrel the action. Any insight into how difficult rebarreling a mini action is? What barrel would produce the best accuracy?

[VASCAR2]

[Oso Polaris]

Any top grade barrel (Kreiger, Bartlein, Brux, Lilja, Shillen, etc). Your biggest challenge is matching the barrel profile and then finding the right barrel blank in stock.

As far as gunsmiths go you just need to ask them if they are set up to handle metric. Most rifles in US are based on Rem700 footprint and as such Imperial standard system for cutting threads.

[Klem]

88,

Yes, barrels shoot some bullets better than others but the difference between 0.75MOA and 2.5MOA is extraordinary. Something is amiss beyond simply barrel harmonics.

[Sinclair]

88,

Yes, barrels shoot some bullets better than others but the difference between 0.75MOA and 2.5MOA is extraordinary. Something is amiss beyond simply barrel harmonics.

Klem is right on something amiss. A member of my gun club has a Beautifully restored Nosin-Nagate
(sp?) that shoots patterns with the bean bags out mid barrel, but shoots MOA groups if he moves them to about 3 inches in front of the trigger guard. Barrel harmonics, I do not know, but I spotted for him one day and it worked, repeatedly, just as I described. Do not despair, Some guns just have to wear in and others wear out.