Headspace question for new Carbon6 prefit barrel

Update: I removed the ejector and verified the extractor was not interfering with the bolt face making full contact with the go gauge base. It was so close to closing but I didn't want to force it closed. I then shined a light into the barrel and noticed a couple of very minute specks in the shoulder area of the barrel. I fashioned a DIY Q-tip onto a cleaning rod as just swabbing a normal patch through the barrel didn't pick them up and was able to remove the specs. I then tried the go-gauge again and the bolt DID close but with a little bit of pressure so it must be just right at the shortest spec possible! I'll load up some ammo and see how it shoots! Here's a couple of pictures of the process:

Ejector removed
0C7B35CB-1055-46B8-BF17-E7661DB88558.jpeg

Go-gauge seated fully against boltface
3701023F-DBDE-48C1-AF56-741828524C98.jpeg

So close to closing…
0FCDC0CA-D790-4D9A-8CBB-FD5298D66260.jpeg

DIY barrel swab
D10D1DA4-8EDA-4836-B740-6728691BA665.jpeg

Finished product
DB8C502B-7167-40AC-B3E1-2D113B836003.jpeg
 
Figured so. But for OP It's more about an ejector that sits proud of a bolt face by a few thou, which isn't uncommon. Sometimes bad machining, sometimes gunk under it. That's why the practice is to always remove ejector at least. And extractor if it isn't a Remington 700 rivet extractor, best to leave that alone.
 
Update: I removed the ejector and verified the extractor was not interfering with the bolt face making full contact with the go gauge base. It was so close to closing but I didn't want to force it closed. I then shined a light into the barrel and noticed a couple of very minute specks in the shoulder area of the barrel. I fashioned a DIY Q-tip onto a cleaning rod as just swabbing a normal patch through the barrel didn't pick them up and was able to remove the specs. I then tried the go-gauge again and the bolt DID close but with a little bit of pressure so it must be just right at the shortest spec possible! I'll load up some ammo and see how it shoots! Here's a couple of pictures of the process:

Ejector removed
View attachment 474751
Go-gauge seated fully against boltface
View attachment 474752
So close to closing…
View attachment 474753
DIY barrel swab
View attachment 474754
Finished product
View attachment 474755
Perfect. Removing that ejector lets a guy feel what's going on, maybe removing the extractor would allow it to close easily, maybe not. I think your good to go now, and a side note, Headspace Gauges are extremely hard material never force them, bad things can happen.
 
Glad to hear all is well, next time, removing stuff from a chamber is best done using compressed air.

Cheers.
Agreed on the compressed air. It was pouring rain and I didn't want to walk out to the garage and use the air compressor. I was very careful and used a bore guide to get the rod close enough to swab the shoulder.
 
Update: I removed the ejector and verified the extractor was not interfering with the bolt face making full contact with the go gauge base. It was so close to closing but I didn't want to force it closed. I then shined a light into the barrel and noticed a couple of very minute specks in the shoulder area of the barrel. I fashioned a DIY Q-tip onto a cleaning rod as just swabbing a normal patch through the barrel didn't pick them up and was able to remove the specs. I then tried the go-gauge again and the bolt DID close but with a little bit of pressure so it must be just right at the shortest spec possible! I'll load up some ammo and see how it shoots! Here's a couple of pictures of the process:

Ejector removed
View attachment 474751
Go-gauge seated fully against boltface
View attachment 474752
So close to closing…
View attachment 474753
DIY barrel swab
View attachment 474754
Finished product
View attachment 474755
Excellent! I figure it was and just had to ask.
 
Now that I've got that part figured out the next question is what bullet/powder combo for a 19" barrel?

Here's what I have so far:

Bullets - Hammer 155's & 169's, Berger 180 HT, 180 VLDH, Hornady 175 ELD-X

Would really like to find some 175 elite hunters… if anyone has some they would want to trade or sell 😁

Powder- N560, RL 23 & 26, H4350, H4381SC, H1000, Retumbo, Ramshot magnum

Primers on hand: CCI 200, 250's, BR2s, 210M, 215M

My goal is mid to long range deer/mule deer/elk to my current comfort range of 600yds hunting. Steel shooting out to 1000yds+


Edit to add: If I did this all over again I would have them cut a longer freebore to run the bullets out further.
 
I've never removed the ejector when headspacing and have done so without any issues afterwards. Maybe I just have the "feel" to it? When doing it on BA's with a barrel nut I have to either make sure the barrel and receiver don't move when tightening the nut or just give a little extra space as when tightening the nut the barrel snugs in and spaces correctly. I'm not a smith, but am a stickler for making sure it's safe! Like for AR's most think it's ok to change the bolt and headspace will remain as is. This is not true on 15's or 10's! I've assembled many in 5.56, 300bo, 6.5gren, 6.5creed, 260rem, 6.8spc, 243win and 308win AR's. With slight variance between mfgs and surface treatments not all are created equal! Some might get lucky not using gauges or just changing bolts. It's all fine until it's not!
 
I've never removed the ejector when headspacing and have done so without any issues afterwards. Maybe I just have the "feel" to it? When doing it on BA's with a barrel nut I have to either make sure the barrel and receiver don't move when tightening the nut or just give a little extra space as when tightening the nut the barrel snugs in and spaces correctly. I'm not a smith, but am a stickler for making sure it's safe! Like for AR's most think it's ok to change the bolt and headspace will remain as is. This is not true on 15's or 10's! I've assembled many in 5.56, 300bo, 6.5gren, 6.5creed, 260rem, 6.8spc, 243win and 308win AR's. With slight variance between mfgs and surface treatments not all are created equal! Some might get lucky not using gauges or just changing bolts. It's all fine until it's not!

So true.

I asked John H at WOP why he sets the headspace at SAAMI plus 2? Simple answer... "so I don't get phone calls why a round would not chamber."

I set the AR15 headspace for the bolt just rotates to battery with go gauge and will not on a clear Scotch tape on the back of the gauge.

On the average I found the coated bolts add about 0.002 to the surface.
 
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I have a c6 barrel in 300wm headspaced by go and no-go gauges from pt&g. I purchased gauges from them for a 6.5prc build on 3/1/23 while awaiting for a barrel to be made........................well, I'm still waiting and did receive the barrel purchased 6 weeks after the gauges were ordered. Barrel took 9 weeks instead of 12, so that's good.
 
Barrel took 9 weeks instead of 12, so that's good.

This is the very reason I bought the 1st lathe and the Bridgeport. After Sandy Hook, I received a barrel over a year from order date. I figure cranking out a barrel from blank is not rocket science. I should be able to figure it out. Still learning, but I am no longer dependent on the gunsmith
 
I've never removed the ejector when headspacing and have done so without any issues afterwards. Maybe I just have the "feel" to it? When doing it on BA's with a barrel nut I have to either make sure the barrel and receiver don't move when tightening the nut or just give a little extra space as when tightening the nut the barrel snugs in and spaces correctly. I'm not a smith, but am a stickler for making sure it's safe! Like for AR's most think it's ok to change the bolt and headspace will remain as is. This is not true on 15's or 10's! I've assembled many in 5.56, 300bo, 6.5gren, 6.5creed, 260rem, 6.8spc, 243win and 308win AR's. With slight variance between mfgs and surface treatments not all are created equal! Some might get lucky not using gauges or just changing bolts. It's all fine until it's not!
Having a headspace gauge being pushed from one side by the ejector, unevenly, sure won't help for perfect headspacing for accuracy. There are gauges designed with a cutout for the ejector and that would be fine. Happy shooting folks!
 

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