Serious feeding problem and sighting in issue.

[Steelpanther86]

Two questions. 1. Does all Grendels suffer feeding issues, my rifle either will jam or just won't properly feeding after every shot. 2. I used Hendershots custom ammo and took a deer with it and tried factory ammo Hornady 123g set and I'm dead center at 25 buy at 100 I'm all over and to the left and this is while using a shooting rest. So is it my grendel don't like Hornady or a barrel problem or maybe my shooting rest isn't heavy enough like I maybe need a Caldwell lead sled.

[sundowner]

Could be the mags or lose scope .

[ETEX HUNTER]

I have never had feeding issues with a Grendel. I have built a few. magazines would be my first thought on feeding. accuracy issues could be many things. scope properly install would be my first thought.

[Klem]

Steel,

Yes, Grendel has a history of magazine issues which you can find by using the Search function. There are a number of fixes and it's hard to say which one your gun needs. Fixes include:

1. Change mag brand.
   
2. Tighten mag latch/release mechanism.
   
3. Polish the mag lips, play with the angle of the lips to present the bullet nose higher.
   
4. File the feed ramps wider and deeper. This includes the anodising on the lower so the ramp into the extension is seamless. A Dremel works best here.
   
5. Change ammunition or play with the OAL if you reload.
   

The strange groups could be because your bullets and their tips are getting dinged from the violent feeding. If they are all off in a particular direction to where you were aiming then likely some other issue. Could be your shooting technique, the build, and of course the scope. Are you using a suppressor?

[LR1955]

SP86:

Let me add this to the mix.

Sometimes AR-15 makers use M-16 feed ramps. The Grendel uses an M-4 feed ramp. Yes, it makes a difference and what you describe indicates that the feed ramp in your blaster may be for an M-16.

By all means, check the magazine latch to make sure it is tight.

Good luck screwing around with magazines. Better bet is to buy a different brand and see if it works.

IF your ammo fits in the magazine with a little space between the tip and front of the magazine, AND it feeds and extracts without problems, most likely your ammo is the right length for function.

Good possibility the Hornady ammo has a different POI than the other ammo you used so having the Hornady stuff group in a different location probably isn't an issue.

Buying a new rest will not solve your problem.

If it was made by a reputable company, you ought to call them and get their advice too.

If it was bodged together by someone in their basement using parts made by unknown companies, then you got your work cut out for you.

LR-55

[VASCAR2]

More specific information on your build might help us diagnose a potential problem. Barrel length, gas port location (carbine, mid length, Rifle length), fixed gas block, adjustable gas system, suppressor in use, buffer and spring in use. The key elements to an accurate AR-15, quality barrel, good trigger and good optic/sights. It is also helpful to know which specific magazine your using in your 6.5 Grendel.

[LRRPF52]

Two questions. 1. Does all Grendels suffer feeding issues, my rifle either will jam or just won't properly feeding after every shot. 2. I used Hendershots custom ammo and took a deer with it and tried factory ammo Hornady 123g set and I'm dead center at 25 buy at 100 I'm all over and to the left and this is while using a shooting rest. So is it my grendel don't like Hornady or a barrel problem or maybe my shooting rest isn't heavy enough like I maybe need a Caldwell lead sled.

I lost count of how many 6.5 Grendel AR-15s I have assembled and tuned.

I just haven’t seen feeding issues as a rule, with maybe 3 exceptions. That included bad magazines and some of the early PPU/Wolf 123gr Soft Point ammo in the 2000s, which was notorious for feeding, accuracy, and pressure problems.

We need more details about what exactly you’re experiencing before we can provide any useful help.

The type of feeding issue, and what your targets look like would be a good start.

Failure To Feed malfunctions can present in different ways.

The most common is actually gas system related, where you have bolt over base FTFeeds, so the bolt rides over the base of the cartridge, but the carrier picks it up and pinches it between the two as it tries to go up the feed ramp, but stops.

This dents the crap out of the brass usually.

Other types of FTFeed involve magazine issues where the bullet tip hits the front wall of the magazine or a poorly-fit feed ramp/upper receiver mating.

Another is where the bullet hits the breech without being aligned with the feed cone in the breech.

Another is where the cartridge doesn’t fit in the chamber properly and doesn’t go fully into battery.

Another is where the rim of the cartridge, when fed from the right presentation in the magazine, gets stuck against the side of the ejector because the ejector was made incorrectly.

Then there is a FTFeed from partial insertion of the magazine, where the magazine isn’t fully seated in the lower receiver, so the cartridge isn’t in-line with the bolt to be stripped properly to go into battery.

Another is actually Failure To Extract where the fired case remains in the chamber, and the fresh cartridge is slammed into the back of it, smashing the projectile into the case.

[just_john]

Have you checked to be sure your barrel is straight with the receiver? And, is it tight in the receiver?

[montana]

https://www.arbuildjunkie.com/ar-15-feed...can-rifle/

This is how you do proper feed ramp work..

https://www.youtube.com/watch?v=Kxz8teLbEPc

[LRRPF52]

Let’s wait to hear specific symptoms from the OP before we start guesstimating about what’s wrong.

We still don’t know what exact type of FTFeed the OP is experiencing.