Re: input on caliber for a new hunting ar
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cox380</div><div class="ubbcode-body">The last two guys who posted must have not read the OP. he mentioned that he already had the reciever so 308 is out of the question and he also said he'd like a 5.56 upper down the road.
To Op I'd go with the one that is easiest and cheapest for you to get ammo. This would be the my biggest consern since youre not looking to reload.
You may also consider mag availability and feeding issues. I could be completely wrong but I believe the 6.8 has <span style="color: #FF0000">propritory</span> mags and the <span style="color: #FF0000">6.5 Grendal will use regular 5.56 mags</span>. I also remember hearing that the 6.5 can give feeding issues more than the 6.8. Also the Grend<span style="color: #FF0000">a</span>l will out perform the 6.8 at distance while the <span style="color: #FF0000">6.8 has more knock down power at closer range</span>. Hopefully someone can elaborate, confirm, or correct me if I'm wrong. This is just what I remember when trying to make the same decicion. </div></div>
Both the 6.8 and Grendel have their own mags, as the cartridges are a larger diameter than 5.56 cases, with different feed lip geometry.
If you do your best to compare similar type/weight bullets between the Grendel and 6.8, the energy matches up at 100yds, with the Grendel starting with 150fps slower mv, and that's out of a 16" barrel for both, then the Grendel retains more energy. Hardly anyone shoots the varmint-weight pills from the Grendel, like the 85gr Sierra, 90gr TNT, 95gr VMAX, or 100gr NBT, because the 120gr class pills perform so much better on game due to energy/sectional density.
There are several new loadings for the 6.8 where they have worked hard to come close to Grendel ballistics, like the Hornady 120gr SST 6.8 load, with a .400 BC, and the SSA 140gr .277 Berger Hunting VLD loaded to 2400fps from a 16".
6.8 barrels are more readily available, but make sure you don't get one with the SAAMI-approved chamber, as it is dangerous with many of the loads on the market.
If you don't reload, and want a barrel now, that leans you towards 6.8 SPC II, or 6.8x43 ARP, or one of the other safe chamberings. Ammo is more readily available for the 6.8 in many areas, however, you need to check your area. In my area, I have Grendel on-the-shelf at several major stores like Cabella's, as well as smaller shops. These are usually the 123gr Hornady AMAX load at around $22-$25 per box. Wolf MPT can be purchased for $13/box from Aim Surplus.
I reload, but do have great sources for ordering ammo from all over, to include AA, Precision Firearms, Palmetto, Aim Surplus, Midway, etc.
As for feeding issues, both cartidges have experienced growing pains, which really are rooted in trying to make a larger diameter case work in a receiver/barrel extension set that was built around the .222 Remington, and never even upgraded to the 5.56 geometry in the late 1950's, when looking at COAL, for example.
For me, the BC's of 6.5mm pills was the deciding factor, and a huge selection of 6.5mm projectiles for both hunting and target work that the .277 bore will never have, but I hand-load almost all my ammo. I also own a .260 Remington and a .270 Winchester, and the .270 rarely leaves the case now, even though it can push a 130gr pill 300fps faster than the .260 Rem.
