Measuring lands in Tikka 22-250

[Diddums]

I was doing some reading on bullet jump and how to measure the lands but the video I watched that showed me how to do it has confused the hell out of me.

It says to remove your firing pin from the bolt so that you can operate the bolt without cocking it. Then seat a bullet and try and chamber it to see how much effort it takes.
Keep searing the bullet deeper until it takes next to no effort to close the bolt and then you know you are just short of the lands.
If I have nothing in the chamber the bolt just falls closed, but as soon as I have anything in the chamber, even an empty resided case, it has to be closed with a bit of force like it normally would. Same thing to open it, nothing in there requires no effort and some effort if there's something in there.

How am I supposed to measure the lands of I can't tell if the bullet is making contact?

[marksman]

full length size the case so there is no effort closing the bolt with the case just effort for the projectile
doing the measurement this way with the firing pin removed has no interference and is the best way for a true measurement
seat the bullet too long and try it in the chamber,
keep adjusting your die back down until you have about 1/4 inch drop to close the bolt fully
this is close enough for a true measurement from the ogive to the case base at this time
down the track your throat will move
use this case as a dummy round for touching the lands
http://www.youtube.com/watch?v=TWmIwPwLyyg&t=160s

[Member-Deleted]

Diddums I've used a 22-250 for years and do the lands thing the old bush way very easy
1...get an empty shell
2....size it
3...put a projectile into the shell just a bit and shade in the projectile in with a niko pen
4....then put bullet into the chamber and bring the bolt to it ever so lightly until it stops
5....remove bullet and check the projectile to see if there are any marks on it as it will scratch the pen ink when it touches the lands
If it has marks on it put it back into the press and push the projectile into the shell further and try it in the chamber again
you may do this may times until you can close the bolt and have no marks on the projectile
You will be able to see when you are getting close to the right length by how far the bolts goes in , when you're close take it very slowly
When the bolt shuts and the marking of the projectile stops then its very close to the lands

Hows that clear as mud hey

[Diddums]

full length size the case so there is no effort closing the bolt with the case just effort for the projectile
doing the measurement this way with the firing pin removed has no interference and is the best way for a true measurement
seat the bullet too long and try it in the chamber,
keep adjusting your die back down until you have about 1/4 inch drop to close the bolt fully
this is close enough for a true measurement from the ogive to the case base at this time
down the track your throat will move
use this case as a dummy round for touching the lands
http://www.youtube.com/watch?v=TWmIwPwLyyg&t=160s

That's what I did but as soon as I have anything in the chamber, even a sized case without a projectile, it seems to take the same amount of force to close the bolt.

[Member-Deleted]

Mate check your brass length it may need trimming , or something in the breach fowling the brass
once a shell has been sized normally it fits ok
Have you used the Full length die before if not check it is not faulty as something is amiss

[Diddums]

Mate check your brass length it may need trimming , or something in the breach fowling the brass
once a shell has been sized normally it fits ok
Have you used the Full length die before if not check it is not faulty as something is amiss

I've used full length dies before with no issues, I even had a case that I trimmed about 1.5mm off and it didn't change at all. Still closed the same way.

[Diddums]

Diddums I've used a 22-250 for years and do the lands thing the old bush way very easy
1...get an empty shell
2....size it
3...put a projectile into the shell just a bit and shade in the projectile in with a niko pen
4....then put bullet into the chamber and bring the bolt to it ever so lightly until it stops
5....remove bullet and check the projectile to see if there are any marks on it as it will scratch the pen ink when it touches the lands
If it has marks on it put it back into the press and push the projectile into the shell further and try it in the chamber again
you may do this may times until you can close the bolt and have no marks on the projectile
You will be able to see when you are getting close to the right length by how far the bolts goes in , when you're close take it very slowly
When the bolt shuts and the marking of the projectile stops then its very close to the lands

Hows that clear as mud hey

Thanks, I'll give this a try.

[Diddums]

But I must say that when I load my rounds to 59.5mm COAL I can still shoot groups under 1 MOA.
I just want to see where they are sitting in regards to the lands.

[duncan61]

Once you get this sorted what distance of the lands do you intend to seat.I seat .8 mm and it seems to work well.I have been told it is for primer expansion so the bullet is on the lands when the powder burns.Thoughts anyone

[Stix]

Im not sure duncan...sorry.

[Stix]

Diddums...you say you feel it with anything in the chamber--but with the firing pin removed, can you chamber a factory round without resistance...?
Do you have a comparitor set to be able to measure the ogive & shoulder of cartridges...?
If so, measure the shoulder of a factory round & a fired case.

I had an issue with mine recently that turned out to be the extractor needing a good heave to get over the case...thankfully it sorted itself out in relatively short time.
I also found mine to have a very short chamber-so short that i can even feel the occasional factory round when i close the bolt.

Id be interested to know your chamber dimensions...

[Apollo]

But I must say that when I load my rounds to 59.5mm COAL I can still shoot groups under 1 MOA.
I just want to see where they are sitting in regards to the lands.

There is a very old and rough method of measuring a bullet to lands seating if you don't have any decent measuring gear.

Now, take note... Very carefully insert a cleaning rod down the bore from the muzzle end without touching the crown/lands. Grab a bullet you are using and position that into the chamber/lands holding it in there with the likes of a pencil/biro/piece of dowel and at the same time place a fine tip pencil/biro mark around the cleaning rod which you should have touching the bullet tip. Might take two people, maybe...but easy to do.

Next is to seat a bullet in a dummy round at the seating depth you have chosen. Do not do this with a Live Round...!!!!
Now measure and/or mark your cleaning rod around the muzzle end like you did with just a bullet... that will give you a rough but good enough measurement of where your rounds are with respect to seated "on the lands".

Better option... buy the correct gear to do the measurements...

[Diddums]

Diddums...you say you feel it with anything in the chamber--but with the firing pin removed, can you chamber a factory round without resistance...?
Do you have a comparitor set to be able to measure the ogive & shoulder of cartridges...?
If so, measure the shoulder of a factory round & a fired case.

I had an issue with mine recently that turned out to be the extractor needing a good heave to get over the case...thankfully it sorted itself out in relatively short time.
I also found mine to have a very short chamber-so short that i can even feel the occasional factory round when i close the bolt.

Id be interested to know your chamber dimensions...

I don't have any factory rounds to try but I'll buy a box for testing, when I was clambering an empty case I would make sure that the extractor claw had hold of the case before I tried to close the bolt so that I wasn't getting any false feedback.

I don't have a comparator set but I may invest in one soon.

[Member-Deleted]

Diddums have you just acquired the gun ? if so check the base of the brass to see if it is marked when it is put into the chamber
and the bolt closed then removed
If it is marked I would be inclined to have the head space checked as there has to be a reason the bolt is giving resistance when being closed
with a freshly sized shell

[Stix]

Can you chamber a fired case...?
Obviously ensure the die is set up correct to fls the cases.

[brett1868]

Diddums, if you're Sydney based get in touch and possibly I can help you out. I've got the Hornady gauges and modified case to do the measurements.

[Diddums]

Diddums have you just acquired the gun ? if so check the base of the brass to see if it is marked when it is put into the chamber
and the bolt closed then removed
If it is marked I would be inclined to have the head space checked as there has to be a reason the bolt is giving resistance when being closed
with a freshly sized shell

I bought it new and the only time I haven't been able to close the bolt is when I had a reloaded case that was .15mm over max length.

I might take it into the gun shop and get them to have a look.

[Diddums]

Can you chamber a fired case...?
Obviously ensure the die is set up correct to fls the cases.

I can chamber anything under 60mm without an issue, even fired cases.

[Diddums]

Diddums, if you're Sydney based get in touch and possibly I can help you out. I've got the Hornady gauges and modified case to do the measurements.

Unfortunately I'm not mate, thanks for the offer though.

I will end up loading for a few different rifles so I think I'll just end up buying the proper gauges.

[Member-Deleted]

Yeah Diddums sounds like you need someone close to you to have a good look at it and measure the chamber up
properly once and for all
Without seeing it all of us that are trying to help you are only running on previous happenings and knowledge although that is most always helpful
but there are times that it is not quiet enough
There could be somebody on here that lives close to you that may help you or even surely the place where you bought the gun would measure it for you if you asked nicely

[Diddums]

I'll take it in town and get it looked at.

[sungazer]

Really for best results you need to remove the extractor plunger as well from the bolt as this is pushing the case forward and gives a false feel. That plunger led me astray because I didn't think it would have such an effect and I didn't really want to try and un pin it

[SCJ429]

Is it easier to find a load and then fine tune it with seating depth. Some chambers will have a long lead which you may not be able to reach with 50 or 55 grain projectiles. You should be able to get that Tikka shooting 1/4 MOA with quality projectiles, Vmax even.

[brett1868]

Diddums, if you're Sydney based get in touch and possibly I can help you out. I've got the Hornady gauges and modified case to do the measurements.

Unfortunately I'm not mate, thanks for the offer though.

I will end up loading for a few different rifles so I think I'll just end up buying the proper gauges.

No worries, if you need cases drilled and tapped then I can do that for the cost of postage

[Oldbloke]

This is how I do it. Do it about 10 times and 3 or. 4 will be the same, that's the coal into the lands. This is because the bullet is inclined to move when doing it.

Another way to do this is to load a dummy round out long but don't resize the fired case. This allows the bullet to move relatively easily within the case so you put it in and close the bolt. It will push the bullet back to the exact length it takes to be resting on the lands. Then carefully remove the case without bumping the bullet and measure it to get the exact length to your lands assuming you didn't knock the bullet and throw off the measurement.

[Diddums]

Ok, so I bought a hornady headspace comparator kit and I've now realised that I made a noob mistake when setting up the full length die by just going off the instructions.

I've now bumped the shoulder on some empty cases and the bolt closes easier than it does on a factory round.
I then played around with trying to touch the lands and I had a pill seated about 2.5mm longer than I usually would and from what i could tell it still wasn't touching the lands.

I have a bullet comparator kit and COAL length gauge on the way so I will measure it up properly soon.

Now what is the least amount that I can seat a bullet in order to get close the the lands?
Is it possible that I won't be able to get close if my rifle has a long throat?

[Stix]

Reaching the lands will depend somewhat on the size of the projectile.
Im guessing the chances are you will be able to reach the lands in a tikka T3 with 50gr & up.
The mag/action for the 22-250 T3 is the same as the 243/308 mag so there is room-a-plenty to seat long.

Im not sure of any given minimum depth to seat a bullet, ive heard many variations like "seat at least calibre depth", but i imagine & have been told (&probably from guys on here too) as long as neck tension & concentricity are not compromised you should be good.
Other more knowledgeable folk here would be better equipped to answer that.

With regard to tight chamering...
The fact you say a sized empty case chambers easier than a factory round is a concern...
You should be able to chamber a factory round with no resistance.... (remove the firing pin before doing this to be safe).

Measure the shoulder of the empty case you have sized, & compare it to a factory.
Any new cases, be it unprimed or factory should chamber without resistance.

[Diddums]

It's not really resistance it more feels like just the locking lugs engaging, but with the chamber empty the bolt just drops closed.
Does anyone on here an a tikka T3x that could try what I have described?

[Stix]

I have a T3...to the best of my knowledge they should be the same.
Im not really sure what im feeling for as i cant feel what you are feeling.
Sorry to not be of use.
Ill give it a crack when i have time mate.

[SCJ429]

I might have missed what projectile you are using but I load for a Tikka T3 SV in 22/250. It shoots 55 grain Vmax in the low .2s at 100 and 1.2 at 300. I load them 2.480. It should get you in the ballpark if you use Vmax.