Touching lands?

[stello1001]

I got a new to me rifle with a Shilen select match barrel. The bolt closes fine on an empty chamber but when chambering a live round, some minor force is required to close bolt down.

I sharpie painted 4 bullets. The two on the left are 168 FGMM and the two on the right are 175 Prime. If I can, i will go shoot her later today but not really sure as of yet I'll have a chance. Fingers crossed though.

There is only one mark, which I would assume only one groove is making contact. Either that, or maybe some thing else is hitting the bullet.
Any thoughts?

Thanks,

S


ETA: forgot to post pics, uploading now...

 

[Supersubes]

That looks way too far up the ogive to be anything in the chamber interfering.

take your caliper and measure the diameter of the bullet where the mark is. Are you single feeding these rounds? They look more like the bullet drag on the chamber wall due to ejector force than anything else. Sharpie up the neck/shoulder too.

 

[2aBaC̶a̶]

If there is something in your barrel that far down you will have a problem if you try to shoot it. Thoroughly inspect it.

That looks more like a mark from feeding or ejecting.

Remove the firing pin and ejector. feed a round into the bolt and slowly close it.

 

[flustercuck]

 

[2aBaC̶a̶]

That's rediculous. How many people are taking their barrel off to find the lands.

There are easier and equally precise ways.

 

[flustercuck]

That's rediculous. How many people are taking their barrel off to find the lands.

There are easier and equally precise ways.

okay

 

[Supersubes]

okay

Do you actually do that? That is rather ridiculous.

 

[Gatorshark]

How many "reported" rounds on the new-to-you barrel? Factory ammo should not give hardly any resistance to chamber. Check head space if you can.

 

[sleeplz]

If you run certain actions it's not ridiculous at all.

 

[stello1001]

Thanks all. I actually shoot factory rifles and factory ammo so I don't have such equipment. There's another video that shows me a more convenient way to measure distance to my lands. Again though, I don't have the equipment to measure.

However, someone in the earlier posts mentioned it's impossible those marks are caused by my lands. I don't know what I was thinking when I imagined it could have been. The diameter of the bullet at the mark is much too narrow and could never make contact.

Based on rifle history and previous owners, there's 500 rounds on this barrel. I put the borescope in there today and it is super shiny and looking very very new to me.

This is an FN SPR action.

I did not get the chance to shoot it today but hoping tomorrow will be the day. I have a feeling it'll shoot well regardless of how it feels when chambering a round but I'll report back.

 

[M1Army]

Looking forward to your report!

 

[Dthomas3523]

Unfortunately, you’ll need some tools to be 100% sure of what’s going on.

To minimally tell if it’s the brass or bullet without measuring stuff:

Remove ejector and firing pin

Pull bullet with plier or something else. Dump powder.

Insert empty brass and see if the bolt falls free with gravity. If it doesn’t. It’s the brass, likely headspace causing the need to use more force. If bolt falls free, it’s not the brass.

If it falls free, put a live round in without the ejector and pin. If it doesn’t fall free (and the empty brass did fall free), then the bullet is in the lands.

 

[dspjaggar]

That's rediculous. How many people are taking their barrel off to find the lands.

There are easier and equally precise ways.

this is what i do when i get a new rifle to start load dev

 

[2aBaC̶a̶]

this is what i do when i get a new rifle to start load dev

Yeah, I've found that and the hornady OAL guage to be very consistent.

 

[stello1001]

I have no idea what to think of the rifle after having shot with it today. Some groups are very nice and some not so nice.

There is one 5 round group on paper with FGMM and one 3 round group on steel with FGMM that have very little vertical. There is a lot of horizontal on them but the wind was blowing so crazy today. The gusts were even stronger.

Anybody care to have an opinion? Also, if anybody wants to try and calculate group size (mine could be wrong) I could always post the original pic.

 

[RLinNH]

Great thread