Working on a new grendel build. Using Faxon match series 20" and before I even have shot this I am getting these scratches on the case. This is factory ammo, Hornady. Also when ejecting using the charging handle, I have to pulled relatively hard to get it to eject. Normal charging handle pulling and it won't eject. The are also rough edges around the rim where the ejector grabs the case. I have the bolt from the recent group buy.
03-24-2018, 11:57 PM (This post was last modified: 03-24-2018, 11:59 PM by grayfox.)
I know this may seem like a dumb question but did you thoroughly clean the chamber and bore before trying a round?
And clean and lube the bolt and bcg...
Did you drop a round down into the chamber (no bcg present), and then turn the barrel up to see if it drops out freely?
That round looks pretty beat up and you've not even started...
wow. Maybe some other guys w/ more experience in these will chime in. I haven't seen one that bad.
Pulling that hard sounds like it may be jamming into the lands but haven't known faxon to have that issue.
Edit: do you mean ejector or the extractor? Sometimes the extractor has rough spots right at the points and they can grab the rim/ hang on to the rim too much. Careful smoothing/filing to smooth them down will help that.
"Down the floor, out the door, Go Brandon Go!!!!!"
Check your mag, it may be scratching the front lip as it is stripped off. Or drop a round in w/o the mag to see if it is still hard to extract.
Extractor marks are common on the rim sanding the points on the extractor will fix that. There are a couple of threads on that issue if you do a search.
Klem Wrote:Magazine scratches are not going to give you that much grief. Sounds like there's something wrong with the chamber. Mangled or swarf still in it.
That is why I suggested to load a round without the mag. If gets same scratches it's in the chamber, if it comes out clean it is most likely the mag.
Thanks for the ideas. I took it apart and going to back together. I also have an Aero upper, ME4 enhanced and it is very difficult to get the Barrel into the receiver. I contacted Aero because the feed ramps of the barrel are not flush with the feed ramps cutouts of the receiver. The best I can tell there is about 0.01 to 0.02 space/ledge left for the barrel to be flush with receiver.
My first email with Aero, they said that not all barrel feed ramps fit flush with the receiver. I have not built a lot of ARs but everyone that I have both feed ramps and cut outs have always been flush. With that amount of difference I wonder about headspacing too. [ATTACH=CONFIG]11404[/ATTACH]
Looking at this picture I would agree. Beyond just talking about the gap there seems to be both radius and dimensional differences between the feed ramps in the extension and in the receiver. Could be edges and/or pointy-protrusions that could impact the case as it inserts... Now this is a bit grainy and only a photo and you will have a much better eyeball view but seems to be several dimensions of mismatch going on between the 2 pieces.
BCM purposely cuts their receivers a bit small to ensure a snug fit, they suggest you heat their recvr and then insert the barrel, let them cool then. If these guys did that too then that might be a good thing. OTOH if it just happened to be mfr variance, who knows if that's good or not.
"Down the floor, out the door, Go Brandon Go!!!!!"
I honestly think it's the barrel causing the scratches. I put another, new factory round into the barrel, it wasn't installed into the receiver. Then I took my BCG and mated the 2 as if they were in the receiver. When I pulled back on the BCG and the round was ejected out I had the same scratches on the case.
I noticed some of the barrel group buys are with Faxon barrels. Is there someone in this forum that has a contact at Faxon? I have been wondering if the receiver is out of spec, due to the barrel not fitting correctly as mentioned above but I am now wondering if it the barrel.
I did freeze the barrel for 8+ hours and it did fit a lot easier into the receiver but it still didn't match up with the feed ramp cutouts on the receiver, looks exactly the same.
12Bravo Wrote:I did freeze the barrel for 8+ hours and it did fit a lot easier into the receiver but it still didn't match up with the feed ramp cutouts on the receiver, looks exactly the same.
Dremel with the chainsaw sharpening bit is perfect for blending feed ramps on these things. You'll get the aluminum of the receiver before you'll ever do anything to the barrel extension - and it looks like that's what your receiver needs.
Where did you buy the barrel?
I had the exact same thing happen to my brass. The nitride was applied over debris or rough chamber.
I contacted Faxon and returned the barrel through FedEx. The barrel was stolen in Cinn Oh and never made it out of the distribution center at FedEx.
My brass looks exactly like it.
I should get my son to help post pictures but haven't got that far into that yet, do you need to use photobucket?
The Faxon bag was tore at the end opposite the Ziploc, I was in a rush and didn't use the Ziploc.
If you have a finished round drop it in the chamber, does it drop and spin. No it will be stuck. Feel inside the chamber with a brass rod and you will feel the debris almost like little pieces of sand.
My barrel went missing 3/6.
Faxon might have a bad batch of barrel chamber issues.
GjGary Wrote:Where did you buy the barrel?
I had the exact same thing happen to my brass. The nitride was applied over debris or rough chamber.
I contacted Faxon and returned the barrel through FedEx. The barrel was stolen in Cinn Oh and never made it out of the distribution center at FedEx.
My brass looks exactly like it.
I should get my son to help post pictures but haven't got that far into that yet, do you need to use photobucket?
The Faxon bag was tore at the end opposite the Ziploc, I was in a rush and didn't use the Ziploc.
Flickr works very well to post photos. Photobucket now requires a paid account for anyone to see your photos.
BluntForceTrauma Wrote:GJG, yeah, that doesn't look like scratching from magazines or extension teeth.
Faxon asked me to send them pictures so I did that today. Haven't heard back yet but knowing someone else has seen the same issue makes me feel better. Those pics look exact the same as what I have on my brass. I have wanted to build a Grendel for a couple years and also get into longer range shooting so this rifle is going to do just that.
We'll see what Faxon has to say.
