223 neck wall thickness

[Dakota Dick]

I have a new Tikka 223 T3x Super Varmint
I have started with 200 Starline brass
I annealed the brass first as I have always found Starline to be very hard brass
I ran the brass through the Redding FL die
Trimmed to standard length 1.750
I loaded up 50 Hornady 55 gr SP with H335 and CCI 400 to run barrel break in (shoot 2, clean barrel, shoot 2 and so on)
After depriming and cleaning that fired brass I checked varous diamensiions and then did a "drop bullet into fired neck" to ensure it would fall through....I tested this on about 10 cases with the same results..it did not drop through. OK, looks like a tight neck chamber.
I triimmed the case neck wall and annealed the brass again The brass wall was .013 to start and I took it down to .0115 and loaded them up with same load above and fired them again.
Bullet dropped a little bit further into the neck but still did not drop through. I even tired one of my 75gr ELDs. A slight tap with the end of my finger and the bullets went through the case mouth
I trimmed 25 of those .0115 cases down to .010, loaded them and will be testing them the end of this week.
I have no indication of high pressure with any of the loads I have fired thus far. So though the chamber neck appears to be tight, it is not show any indications of creating high pressure issues with the .013 or .0115 wall thicknesses.
I was wondering if anyone else has experienced this tight chamber neck in the Tikka?
I have always done the fired case bullet drop test on the various rifles I have owned and up till this point, have not expereneced this tight of a chamber neck before.
The OD of the fired cases has been consistant so trimming the outside of the neck is the obivious solution to ensuring the expanded neck is fully clearing the bullet and not interfering with the bullet release.
Yep, I understand about the brass spring back... but like I said, never had the issue of the bullet not dropping cleanly through a fired neck.
I expect/hope the bulllet will drop cleanly though the .010 trimmed neck. I am sure the neck tension on the bullet will be or has alread been reduced and I am not sure I want to go any further with thinning the neck wall.
Thoughts/Comments?

 

[Straightshooter1]

I have a new Tikka 223 T3x Super Varmint
I have started with 200 Starline brass
I annealed the brass first as I have always found Starline to be very hard brass
I ran the brass through the Redding FL die
Trimmed to standard length 1.750
I loaded up 50 Hornady 55 gr SP with H335 and CCI 400 to run barrel break in (shoot 2, clean barrel, shoot 2 and so on)
After depriming and cleaning that fired brass I checked varous diamensiions and then did a "drop bullet into fired neck" to ensure it would fall through....I tested this on about 10 cases with the same results..it did not drop through. OK, looks like a tight neck chamber.
I triimmed the case neck wall and annealed the brass again The brass wall was .0013 to start and I took it down to .00115 and loaded them up with same load above and fired them again.
Bullet dropped a little bit further into the neck but still did not drop through. I even tired one of my 75gr ELDs. A slight tap with the end of my finger and the bullets went through the case mouth
I trimmed 25 of those .00115 cases down to .0010, loaded them and will be testing them the end of this week.
I have no indication of high pressure with any of the loads I have fired thus far. So though the chamber neck appears to be tight, it is not show any indications of creating high pressure issues with the .0013 or .00115 wall thicknesses.
I was wondering if anyone else has experienced this tight chamber neck in the Tikka?
I have always done the fired case bullet drop test on the various rifles I have owned and up till this point, have not expereneced this tight of a chamber neck before.
The OD of the fired cases has been consistant so trimming the outside of the neck is the obivious solution to ensuring the expanded neck is fully clearing the bullet and not interfering with the bullet release.
Yep, I understand about the brass spring back... but like I said, never had the issue of the bullet not dropping cleanly through a fired neck.
I expect/hope the bulllet will drop cleanly though the .0010 trimmed neck. I am sure the neck tension on the bullet will be or has alread been reduced and I am not sure I want to go any further with thinning the neck wall.
Thoughts/Comments?

FYI: 13 thousandths is .013, not .0013.

You should be ok with the .010 neck thickness. Just be aware that donuts at the neck shoulder junction are likely to form quicker due to the difference in the shoulder's thickness and the neck thickness. That shouldn't be a problem if you're seating with the bearing surface above that area..

 

[Dakota Dick]

FYI: 13 thousandths is .013, not .0013.

You should be ok with the .010 neck thickness. Just be aware that donuts at the neck shoulder junction are likely to form quicker due to the difference in the shoulder's thickness and the neck thickness. That should be a problem if you're seating with the bearing surface above that area..

Thanks for the comments...yep, got carried away with the 000000s

 

[Dakota Dick]

Edited the initial post to correct the 000000 issue...thanks again.

 

[Webster]

I have a new Tikka 223 T3x Super Varmint
I have started with 200 Starline brass
I annealed the brass first as I have always found Starline to be very hard brass
I ran the brass through the Redding FL die
Trimmed to standard length 1.750
I loaded up 50 Hornady 55 gr SP with H335 and CCI 400 to run barrel break in (shoot 2, clean barrel, shoot 2 and so on)
After depriming and cleaning that fired brass I checked varous diamensiions and then did a "drop bullet into fired neck" to ensure it would fall through....I tested this on about 10 cases with the same results..it did not drop through. OK, looks like a tight neck chamber.
I triimmed the case neck wall and annealed the brass again The brass wall was .0013 to start and I took it down to .00115 and loaded them up with same load above and fired them again.
Bullet dropped a little bit further into the neck but still did not drop through. I even tired one of my 75gr ELDs. A slight tap with the end of my finger and the bullets went through the case mouth
I trimmed 25 of those .00115 cases down to .0010, loaded them and will be testing them the end of this week.
I have no indication of high pressure with any of the loads I have fired thus far. So though the chamber neck appears to be tight, it is not show any indications of creating high pressure issues with the .0013 or .00115 wall thicknesses.
I was wondering if anyone else has experienced this tight chamber neck in the Tikka?
I have always done the fired case bullet drop test on the various rifles I have owned and up till this point, have not expereneced this tight of a chamber neck before.
The OD of the fired cases has been consistant so trimming the outside of the neck is the obivious solution to ensuring the expanded neck is fully clearing the bullet and not interfering with the bullet release.
Yep, I understand about the brass spring back... but like I said, never had the issue of the bullet not dropping cleanly through a fired neck.
I expect/hope the bulllet will drop cleanly though the .0010 trimmed neck. I am sure the neck tension on the bullet will be or has alread been reduced and I am not sure I want to go any further with thinning the neck wall.
Thoughts/Comments?

Don't understand your drop bullet test. I question whether dropping a bullet into the neck is a valid way to determine what neck thickness you need. A factory rifle should never have to turn the neck to chamber a round. A loaded case with a neck of .0135" thickness should always chamber with no resistance. Get a chamber blue print and look at the neck diameter and compare to a loaded round o.d. I read your post pretty quick I think I understand what you’re doing. There should always be room for the case to expand in the chamber with unturned brass. 50 years of reloading I don't think I ever looked to see if a bullet would drop into a fired case. I would guarantee you that the case expands enough to release the bullet.

 

[Zero333]

Who cares as long as it doesn't show pressure and it shoots good.

Sometimes things are a little wonky,.. don't let it get to your head too much.

I've had plenty of farctory and aftermarket barrels do the same as yours, but they worked and I had no issues.
The drop test is only valid if you're having pressure sing issues.

Load them, shoot them, and have lot's of fun !
That's the whole point at the end.

 

[markm87]

We run a Tikka bolt gun in 223, and load 88 ELDMs 2.50" long. I've not noticed trim length to be an issue. I have my Giraud set to .010" over spec to minimize trim and get a little more neck contact on the bullet.

 

[243winxb]

drop bullet into fired neck

Poor test. Low pressure will not always expand the necks.

Do measure a loaded rounds outside neck diamer. Should not be larger then a maximum of .253"

This allows .002" or more clearance in the chamber.

New brass may come with a slight donut.


Photo from AMP Annealing.

 

[fkimble@charter.net]

Also when ejecting a fired case, the strong ejector spring will push the case to the side. When neck clears back of chamber, it is slapped towards the side opening. This can an will malform the neck. When ejecting a case to be measured or drop tested, put your finger on the side of the case and hold it straight until the neck has cleared the ejection port. This will take a couple tries til you get the hang of it. Also works great when you get a bullet stuck in the throat. Just point barrel straight up and ease the bolt open. Powder will stay in the case,as long as its pointed up. Prevents the dreaded power every where.

Frank

 

[K22]

I have three Tikka 223 Rems, one the varmint model.

If I read your post correctly, you are experiencing no pressure signs, no chambering problems or no extraction problems. You didn't indicate how well the rifle is shooting on target. How is it shooting?

I totally agree with post # 5, you should never have to turn necks in a factory rifle for properly functionality. I know some do it to improve accuracy and I would not dispute than because I don't know because I have never had to do it to meet my precision requirements for varmint and predator hunting.

All my Tikka's shoot outstandingly well with tuned reloads. The 8" twist 223's especially shoot the 60 Vmax with Varget or H4895 very well, in the 1/2 moa range.

If your rifle and reloads are functioning properly and shooting well then don't "fix" them or don't create a problem to fix.

 

[jepp2]

Thoughts/Comments?

I would estimate 2/3 to 3/4 of my rifles will fail the test you are performing. On some I can tell the tip of the mouth isn't quite as open as the remainder of the case neck. On most of these I KNOW the chamber diameter. I don't even perform the test.

What I am interested in:
- loaded case neck OD (measured with a micrometer that reads to 0.0001)
- fired case neck OD (measured the same way)
- sized case neck OD (yep, measured the same way)
- expanded case neck OD (you know by now)
This gives me an idea of the amount of work I put into the case during the firing/sizing cycle. This also tells me a lot about how I want to run my sizing portion of things. Folks put too much confidence in measuring with dial calipers on what accuracy they can consistently provide.

 

[Frankm]

+1 on case mouths possibly being dented when ejecting AND

Were your loaded/fired rounds within a couple grains of max type pressure? ( you may have a low pressure load that’s not fully expanding case neck)

 

[Coyotefurharvester]

I know I can't be that precise, my measuring equipment is +,- 0.001, even my 0.0005 caliper says +,- 0.001 in the specifications.

 

[Webster]

+1 on case mouths possibly being dented when ejecting AND

Were your loaded/fired rounds within a couple grains of max type pressure? ( you may have a low pressure load that’s not fully expanding case neck)

I don't think he had any problem. He just made up a story about a problem that didn't exit.

 

[Webster]

+1 on case mouths possibly being dented when ejecting AND

Were your loaded/fired rounds within a couple grains of max type pressure? ( you may have a low pressure load that’s not fully expanding case neck)

If a low pressure load is 50,000 PSI do you think 50,000 PSI won't expand the case enough?

 

[joshb]

First thing you should have done is cast the chamber. With turned necks, you’ll need the right bushings for your die. If your die isn’t a bushing die, you might have a problem getting good neck tension.

 

[Frankm]

I d say possibly as many variables involved. Brass hardness, neck clearance due to different brass thickness, spring back again based on individual brass composition, etc.

More than 1 variable at work. I ve seen some loads with “good” pressure still leave brass a little tight.