what is a GOOD group for Grendel?

[LR1955]

I can't say how it will work for you for me a load that has shot well for me in every barrel I have had in the Grendel. I have or had AA 24" Overwatch (my first barrel in Grendel), Satern 24" cut rifled, Proof Research 20", Proof Research 18", and a Rainier Ultra Match 16" (Criterion chambered by Craddock I understand).

AA brass (Lapua) annealed every time
450's (Wolf SRM are great too but....)
31.2 LeverRevolution
120 SMK (mine are all pointed)
.025" off of jam (each barrel is/was slightly different)
This load has been used by me to 600 yards and it was great there too. I full length size without the expander and use a 21st Century mandrel die w/.2615" mandrel.

This is a stout load but has been safe in all of my rifles. My brass will go beyond 7 firings and not lose a primer pocket. The 120 SMK is not a sexy bullet as far as BC is concerned but it tunes easliy. A Berger 120 BT is even better for easy accuracy but are not existent and I was not smart enough to buy a pile some years back.

I just built a 16" Grendel (Rainier Ultra Match) and it appreciates this load too but it's not surprising to me. As usually mentioned, back off a touch and work back somewhere near there if your rifle allows it. I can't say how Starline will hold up to this load.

I usually shoot my Grendel AR's off of a Randolph front rest and either a Protektr or Edgewood rear bag. So typically I treat them similar to a Benchrest rifle. That said, I "hold" them. When I ease up and start to not hold them, groups open up.

120 Match King is over half of it. I have said it over and over again here. If your barrel doesn't shoot well with a 120 Match King, get a new barrel. I can't say that I have had any problems getting a 120 MK to shoot 3/4 minute with a decent barrel and that is with a variety of powders, loads, seating depths.

Oh yes, I don't anneal, rarely polish, don't do anything to the primer pockets, and my seating depth is such that the ammo feeds easily from my magazines and does not touch the lands when chambered. I do use Lapua brass though. Get a good fifteen to twenty shots per piece. I do trim once in the life of the brass although it never really needed it. I do not hot load a Grendel. Hot loading a Grendel or any AR-15 round of ammo is unnecessary for great performance.

I shoot off of a couple of G.I. sand bags. Totally adjustable and easy to form into a excellent rest. Can exert a lot of force on them and they won't break, like every other rest I have used. Easy to pack, too. Dump out the sand or cat litter and fold up. Oh yes, I put a strip or two of Green Tape across the middle of the front one so my forend doesn't tear up the bag. Good for bench, good for prone. Will never go wrong with them.

LR-55

[muvef]

I can't say how it will work for you for me a load that has shot well for me in every barrel I have had in the Grendel. I have or had AA 24" Overwatch (my first barrel in Grendel), Satern 24" cut rifled, Proof Research 20", Proof Research 18", and a Rainier Ultra Match 16" (Criterion chambered by Craddock I understand).

AA brass (Lapua) annealed every time
450's (Wolf SRM are great too but....)
31.2 LeverRevolution
120 SMK (mine are all pointed)
.025" off of jam (each barrel is/was slightly different)
This load has been used by me to 600 yards and it was great there too. I full length size without the expander and use a 21st Century mandrel die w/.2615" mandrel.

This is a stout load but has been safe in all of my rifles. My brass will go beyond 7 firings and not lose a primer pocket. The 120 SMK is not a sexy bullet as far as BC is concerned but it tunes easliy. A Berger 120 BT is even better for easy accuracy but are not existent and I was not smart enough to buy a pile some years back.

I just built a 16" Grendel (Rainier Ultra Match) and it appreciates this load too but it's not surprising to me. As usually mentioned, back off a touch and work back somewhere near there if your rifle allows it. I can't say how Starline will hold up to this load.

I usually shoot my Grendel AR's off of a Randolph front rest and either a Protektr or Edgewood rear bag. So typically I treat them similar to a Benchrest rifle. That said, I "hold" them. When I ease up and start to not hold them, groups open up.

See highlighted above... Give or take a couple .001", this is were I've always found the best accuracy in my Grendel barrels.

As far as accuracy expectations go, It just depends how much the barrel costs. A $300 barrel I would expect to get bulllet holes touching with the proper load developement. Budget barrels usually provide budget groups, not alwys, but usually.

[DHD]

I didn't search long and hard for the seating depth for the 120 SMK (.025" off). They aren't too particular about it in my opinion. I consider the 6.5mm 120 SMK the same as a 30 cal 168 SMK. Not a high BC, not designed for really long range, not picky about velocity, and not picky about seating depth but they shoot well across the board.

Because I just like to tinker with stuff, I always look for something better. My newest testing has been the 105 BK's. So far they are not doing well. If I were you, I wouldn't waste time with them. Not worth the effort. Yep, money down the drain. Move along and keep your barrel life. Horrible bullets that even look ugly and you don't want ugly bullets....

[Rugerfan.64]

6.5 Gr 120 Matchking 4-11-2020.jpg I shot this one several years ago, and I really havent shot the rifle much since then. I have a 6 BR to play with now. This rifle was a budget frankengun I put together for my daughter. I run AR Comp, CCI 400's and Sierra 120 gr Prohunters. It'll regularly shoot into a 1/2" or so, and rarely ever goes over 1" at 100 yds. Plants deer in their tracks for her. Its PSA blem upper and lower, Satern 24" barrel. Its heavy, but we dont walk around with it, just sit in the shoot house so thats not an issue. I once worked up a load with Sierra 120 Matchkings, out of the 5 loads I'd put together for 5 shot groups, only one of them shot over an inch at 100. The Matchkings didnt shoot as good as the Prohunters, but they are fun to shoot. This is off of bags front and rear.