Measuring lands in Tikka 22-250

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Re: Measuring lands in Tikka 22-250

Post by Diddums » 03 May 2018, 2:16 pm

brett1868 wrote: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.
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Re: Measuring lands in Tikka 22-250

Post by Member-Deleted » 03 May 2018, 2:41 pm

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
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 03 May 2018, 3:06 pm

I'll take it in town and get it looked at.
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Re: Measuring lands in Tikka 22-250

Post by sungazer » 03 May 2018, 4:10 pm

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
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Re: Measuring lands in Tikka 22-250

Post by SCJ429 » 03 May 2018, 9:54 pm

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.
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Re: Measuring lands in Tikka 22-250

Post by brett1868 » 04 May 2018, 12:47 pm

Diddums wrote:
brett1868 wrote: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 :)
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Re: Measuring lands in Tikka 22-250

Post by Oldbloke » 05 May 2018, 7:47 am

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.
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 08 May 2018, 9:40 pm

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?
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Re: Measuring lands in Tikka 22-250

Post by Stix » 09 May 2018, 1:11 am

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.
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 09 May 2018, 7:23 am

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?
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Re: Measuring lands in Tikka 22-250

Post by Stix » 09 May 2018, 11:34 am

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.
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Re: Measuring lands in Tikka 22-250

Post by SCJ429 » 09 May 2018, 7:41 pm

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.
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 10 May 2018, 4:23 pm

SCJ429 wrote: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.


I've been using Hornady Z-Max, Sierra Blitz Kings and now trying to work up a load for Sierra SBT Game Kings. I have only loaded all these to just below 60mm COAL which is about 3mm shorter than your load.
The best group i have managed is .5in @ 100m for a 5 shot group, ill be interested to see how i go when i measure it up properly.
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 10 May 2018, 4:24 pm

I received my COAL gauge and bullet comparator kit today so I'm going to measure it all up tonight.
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Re: Measuring lands in Tikka 22-250

Post by Member-Deleted » 10 May 2018, 9:02 pm

Diddums mate have you blued the backs of the locking lugs to see if they both are touching the same amount and at the same time when
the bolt is closed
some times it is possible for one to touch harder than the other and probably feel like a little resistance with a shell inserted into the chamber
and the bolt being closed
Just and after thought as I had a remmy with that problem quiet a few years back the gunsmith fixed it by putting grinding paste behind the one
hitting the hardest till it moved back then he lapped them both but after doing that you test the head space again although it should be good as
paste doesn't remove much metal
Just a thought mate
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 10 May 2018, 9:40 pm

grandadbushy wrote:Diddums mate have you blued the backs of the locking lugs to see if they both are touching the same amount and at the same time when
the bolt is closed
some times it is possible for one to touch harder than the other and probably feel like a little resistance with a shell inserted into the chamber
and the bolt being closed
Just and after thought as I had a remmy with that problem quiet a few years back the gunsmith fixed it by putting grinding paste behind the one
hitting the hardest till it moved back then he lapped them both but after doing that you test the head space again although it should be good as
paste doesn't remove much metal
Just a thought mate


No I haven't tried that but I'll give it a go.
No harm in checking.
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 10 May 2018, 9:51 pm

So I measured my chambers COAL tonight and it was 2.134", which is quite crazy considering that i had been loading my rounds .106" (2.7mm) shorter than my COAL.
I'm looking forward to seeing how they go.

I also measured my headspace and I tried to bump it back about .004 but I was having a hard time getting it consistent.
Is it normal to have variances in headspace measurements by +/- .001

Also should I be concerned it the projectile is only seated about .196 - .236 (5-6mm) in the neck?
They didn't feel loose or anything.

I did have one casualty though.
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Re: Measuring lands in Tikka 22-250

Post by Stix » 11 May 2018, 12:08 am

I assume when you mean your chambers coal you mean the measurement to the ogive when the bullet is touching the lands...?
Keep in mind this measurement will be different for every type & even often each different batch of bullets.

Im not sure what others do, but i only bump the shoulder back enough so it chambers without resistance-or ideally when i can just feel it as per marksman's suggestion when finding the lands (feeling for same but with shoulder of case, not projectile)--so .001"-.0015" shorter is plenty...i think .004" is too much bump--your just working the brass unnecessarily & risking different results from load testing due to smaller case capacity with such a large bump.

Just check cases in the chamber as you wind the die down & lock the die when the cases are just chambering ok as per above--i like to try a few cases each time you change the die just to be sure.

Headspace/case shoulder measurement variations--do you mean variations from sizing a case, or measuring a once fired case...?

Either way i easily get variations of .001" & believe its ok.
however id suggest only neck sizing once they are formed to the chamber.
Once formed to the chamber i still sometimes get variances of .001", but i have sometimes found new cases take a couple of firings to fully form. (Or more to the point they probably spring back less after a couple of firings).

I think 5-6mm of the bullet seated in the case is fine mate-thats basically calibre depth, & ive seated them less than that.

That is a cracker of a casualty...ive had the odd dent in the shoulder from too much lube build up, & a split neck from lack of lube, but that ones a wee ripper...id frame it & give it pride of place on the top shelf of the loading bench...!!!
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Re: Measuring lands in Tikka 22-250

Post by Diddums » 11 May 2018, 7:16 am

Stix wrote:I assume when you mean your chambers coal you mean the measurement to the ogive when the bullet is touching the lands...?
Keep in mind this measurement will be different for every type & even often each different batch of bullets.
yes, I measured it with a bullet comparator kit. I did measure about 10 projectiles from the ogive and there was a bit of variation by a couple of thou.

Im not sure what others do, but i only bump the shoulder back enough so it chambers without resistance-or ideally when i can just feel it as per marksman's suggestion when finding the lands (feeling for same but with shoulder of case, not projectile)--so .001"-.0015" shorter is plenty...i think .004" is too much bump--your just working the brass unnecessarily & risking different results from load testing due to smaller case capacity with such a large bump.

Just check cases in the chamber as you wind the die down & lock the die when the cases are just chambering ok as per above--i like to try a few cases each time you change the die just to be sure.

Headspace/case shoulder measurement variations--do you mean variations from sizing a case, or measuring a once fired case...?
I mean that when I'm sizing the cases they were all coming out of the press exactly the same length, there was a bit of variation.

Either way i easily get variations of .001" & believe its ok.
however id suggest only neck sizing once they are formed to the chamber.
Once formed to the chamber i still sometimes get variances of .001", but i have sometimes found new cases take a couple of firings to fully form. (Or more to the point they probably spring back less after a couple of firings).

I think 5-6mm of the bullet seated in the case is fine mate-thats basically calibre depth, & ive seated them less than that.
I wasnt sure as they are a lot longer than the max cartridge length in a reloading book

That is a cracker of a casualty...ive had the odd dent in the shoulder from too much lube build up, & a split neck from lack of lube, but that ones a wee ripper...id frame it & give it pride of place on the top shelf of the loading bench...!!!
I pushed on the press a little too much and that was the end result.
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Re: Measuring lands in Tikka 22-250

Post by sungazer » 11 May 2018, 8:56 am

Yes that is am issue with Hornady seating dies. a lot of seating dies you can adjust so the shell holder touches the die but not one of these. You have the seating die wound down to far it needs to be wound out a few turns. It is also a die that will put a crimp on if in too far which you dont really want either. I assume you re read the instructions and worked it out?
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Re: Measuring lands in Tikka 22-250

Post by Stix » 11 May 2018, 7:20 pm

Not sure if this will help diddums...
But one thing i do for consistant measuring, when fitting the hornady measuring equipment to calipers...

I leave the grub screws loose until everything is pushed up together/calipers are closed.
With thumb pressure still on closed calipers i then do up the grub screws & zero. It just helps to ensure no movement can happen.

You get to know certain measurements for certain rifles & bullet batches in your head & soon know if the comparitor bits aren't in the right spot on the calipers.
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