Gunsmithing TL3 in 223 wil not CRF from the mag

[hoguer]

My new TL3 223 with Accurate Mags isn’t picking up the rounds correctly from the magazine. The first 8 rounds will feed half way into the face of the bolt, and be centered the rest of the way upon clambering an the last 2 rounds are popped out of the mag and have to be forced into the extractor with the bolts forward movement. Any thoughts? Is it just a mag issue?

 

[Bugholes]

I might be able to help you if you wanted to give me a call one afternoon

 

[Skunkworx]

Is it a magazine spring tension issue? The first few rounds will have more spring pressure pushing up on the shell. The last few will be progressively lighter until the end.

Have you tried stretching the spring out a little to add my tension?

 

[Codiekfx400]

I would try a mdt mag.

 

[hoguer]

Thanks Greg I’ll give you a ring on Wed when I get home to look at the rifle.
Skunkworks- yes mag tension is a apparent factor as it won’t even half feed into the extractor on the last two, but the first few rounds are still not feeding completly into the bolt face.
I have not yet tried to stretch/modify the mag or tried any other mags

 

[hoguer]

Uploaded a video of the last round feeding issue to YouTube.

 

[Xander3Zero]

I had pretty much the same issue with my TL3 recently. Your's actually looks to be "closer" to properly functioning than mine was with my mags.

Bighorn thought the entrance chamfer to my chamber was causing the round to stick. I did a feed test with the extractor removed from the bolt head and it fed flawlessly, smooth as butter. Greg was the one who chambered my barrel and was generous enough to let me ship him the rifle to troubleshoot a bit.

Right off the bat he was able to get it to feed with some of his mags, but I have 2 MDT mags (1 modified, one stock) and a Accurate Mag that all won't feed well/smoothly with the CRF. Greg also increased the size of the entrance chamfer which had no improvement. I bought a push-feed 223 bolt head from Bighorn (they make them for 223AI apparently) and I am now having much more success feeding out of my mags, and also single-feeding rounds on top of mags.

I am pretty sure that with some fine-tuning I could get the mags feeding better with the CRF, but I am just running it as a push-feed setup for the time being. Really seems to me like the angle of the small 223 cartridge entering the chamber is a bit too steep to slip under the extractor smoothly, but many people are running 223 TL3 without issue, so apparently I am the minority.

Keep us updated with your situation.

 

[Sixfivesavage]

I'm curious what brass the people with problems are using vs people who are having success. Also curious as to what the oal is to see if there's any similarities.

 

[bohem]

We've done a number of them and the MDT mags seem to be the ticket. I still have some of the AI mags that I use and those worked well for me. The question of presenation to bolt face is also something to consider. You need enough presentation to strip the round but not so much that it runs into the extractor while it's still in the magazine.

I have a push feed TL action c.2010 that runs like absolute butter. With the little diameter on the 223 it is just super smooth. The CRF has a lot of benefits but on action geometries originally designed around 473 and 532 bodies the little 380 body size does have some trade-offs.

It's an interesting approach that @Xander3Zero took to swap the TL3 over and run a push feed head on his TL3. Have you removed the ejector for that conversion too?

Typically you want to see:

appx 0.04" depth on the chamber mouth chamfer with a 60 degree angle
presentation to bolt face that keeps the receiver raceway circle and the primer pocket circle just inside of tangent; aka you can just see the top edge of the primer pocket when you look in from the back.
open the front feed lips a tiny bit to bring the nose of the cartridge up a little bit and present towards the chamber mouth earlier.

 

[earthquake]

I'm curious what brass the people with problems are using vs people who are having success. Also curious as to what the oal is to see if there's any similarities.

My TL3 with Accurate 10 & 5 round mags run flawlessly. I've been running Copper Creek ammo at matches. I believe it's Winchester brass, with a Berger 77-gr OTM seated short. I can measure OAL later if it might be helpful. @bohem (PVA) built the gun.

 

[Xander3Zero]

@bohem Do you mean remove the mechanical ejector? The push-feed bolt head that I got from BH has a slot for the mechanical ejector, similar to the CRF head. The only thing I needed to do for the conversion is swap the bolt head out. The push-feed bolt heads are also symmetrical and can be run on LH or RH actions. I can upload a pic of the bolt head later.

Also I would say that my setup has achieved all of those things you mention as being important for the CRF actions. Not sure if you remember, but we talked on the phone a few weeks ago about my issue and you mentioned the chamfer stuff to me.

appx 0.04" depth on the chamber mouth chamfer with a 60 degree angle
Greg definitely increased the size of the chamfer (as much as he could safely do without leaving too much unsupported case), but I believe it is just a 45° chamfer.

presentation to bolt face that keeps the receiver raceway circle and the primer pocket circle just inside of tangent; aka you can just see the top edge of the primer pocket when you look in from the back.
While looking through the back of of the receiver with the bolt removed and mag inserted, you can just see the top of the primer pocket.

open the front feed lips a tiny bit to bring the nose of the cartridge up a little bit and present towards the chamber mouth earlier.
I have a modified MDT mag that has exactly this type of modification. I relieved the inside of the front of the feed lips to allow the cartridge to angle up and release from the magazine a little sooner.

Despite this, I still have poor feeding with the CRF. It seems like the cartridge jams between two points as it enters the chamber. The first point is the body of the case contacting the lower edge of the chamber mouth, and the second point is the case head contacting the bolt face and attempting to slide under the extractor. Like I said, Greg did have this thing feeding with some of his mags, so I know that the potential solution is to probably just go to town on my mags. I'm enjoying the push-feed and would rather spend my weekend shooting than modifying $40-60 mags with the small chance that I will get it to feed CRF as well as the push-feed lol.

The fact that everything works flawlessly with the CRF extractor removed, makes me think that another possible solution would be to try and modify the undercut of the extractor slightly to give more clearance for the case head to slip under.

 

[padom]

I had some issues with my 223 TL3 stripping rounds from the mag a while back. Josh was over and stretched the spring in my Accurate mag to give a little more tension. My issues wasnt hanging up feeding into the chamber, it was having issues stripping the round from the mag all the way. After stretching the spring some its been running flawlessly for many months now.

 

[hoguer]

thanks for all of the responses. I have a few AICS mags ill try out and also attempt to increase the spring tension a bit on the accurate mags. @Bugholes I will probably give you a call tomorrow to chat about your input.

 

[Bugholes]

What I saw was magazines with your typical "cartridge angled upwards" presentation caused the worst feeding with the CRF bolt head. When cartridges were left with a "bullet lower" angle they fed better
Either way, a narrow cartridge such as the 223Rem has got further to go when it comes free from the mag feed lips entering a flat breech face barrel