22-250 AR10... because I want problems

[Wolfdog91]

We need to get you a Garmin chrono. Be good and see if Santa brings one....

With what factory ammo is costing, and how easy it is to take data with the Garmin, it will pay for itself after a while.

If you only shoot short range, then it doesn't really matter unless you are just curious about your inferred pressure and the ballistics. (Ignore me because I can spend your money faster than you can make it....)

Keep that BCG well lubricated till she brakes in and inspect while you clean. It takes more rounds to brake in a rougher unit than a good one, so expect this to take around 200 rounds.

Semi Autos are dirty creatures to clean, so get yourself a workflow and the right tools for that job and don't damage (scrape too hard) the parts that are supposed to be a tight fit like the tail of the bolt. Good Luck, YMMV

Yeeepp I'm looking hard at one right now. What I do now is soot with and without it at first and see if there much of a difference and if not I'll just run with it and when I get a group that has good numbers or looks good just to be sure Ill shoot another groups or two without the magneto to confirm

 

[RegionRat]

If your brass has that bright ring you show in your snapshot, are you familiar with using a probe made from a bent paperclip or stiff wire? A wet tumble and borescope in the cases is also a way to eliminate the worry that those rings are from the brass "necking" down in that area in what is called incipient case head separation.

I have had ammo boxes buff the brass at about the same place, so play it safe and double check to make sure that brass is okay. Good Luck and in for the range reports.

 

[Wolfdog91]

If your brass has that bright ring you show in your snapshot, are you familiar with using a probe made from a bent paperclip or stiff wire? A wet tumble and borescope in the cases is also a way to eliminate the worry that those rings are from the brass "necking" down in that area in what is called incipient case head separation.

I have had ammo boxes buff the brass at about the same place, so play it safe and double check to make sure that brass is okay. Good Luck and in for the range reports.

Your ammo box statement made me think a lil and realized it could be from my trimmer ! Noticed about all the brass I use this thing on end up with one of those rings right where the lil collet makes contact

 

[Wolfdog91]

And lil project update :
picked up some of this magical powder eveyone keeps talking about and a box of these 52 gr BTHP's. Think they will be the best thing I could ask for given all the constraints a 1:14 twist gives a guy. But yeah this 380 is supposed to be the best thing since sliced bread for the 250

Next to one of the 55gr SP's... Which onna side note , I was reading and apparently the cannulated 55gr HP's work better , terminally wise ..... Folks think it's because the cannular works kinda like this deal on a nosler partition....KINDA ...... Sorta kinda ..... In a very liberal sense lol



And with more reading I see the 55gr is a favorite across the pond seen a lot of talk from Brit and Kiwi deer stalkers liking them . Especially because there usual lack of a pass though


Anyhow will say I noticed the 52gr BTHP's have a bit of a bigger HP then something like my 69gr BTHP's

 

[tbs]

H380 load I used in my Shilen 14 twist barrel. Wow this is 27 years ago!

 

[Wolfdog91]

Alright alright alright new bullet time.

BTW :THIS IS NOT A HOW TO IM NOT AN EXPERT.. I'm just some goober documenting his lil adventure nothing I say is how you SHOULD do something..just what I'm doing please don't follow me step by step because you might blow your face off .
Anyhow

So first I gave it a cleaning , I haven't cleaned it since I first got it so it's got 70 odd rounds with of carbon and copper built up
Threw it in the vice and squirted a good bit of hoppes down the barrel and just let it eat over night while I was doing other stuff
Then did my usual cleaning deal , hopes dry patches , scub with JB bore paste yadda yadda y'all know the deal

And a quick look on the inside


Found these hieroglyphics in there lol

And looks like this cleaned up nicely

 

[Wolfdog91]

New bullet = new seating depth so making a little split case to find my jam..... Now let's be clear I AM NOT jamming my bullet nor want to I just wanna find my rifling SO I CAN STAY OFF OF IT
Any way sized and prepped case Dremel

So , how this works , the cut allows you to ad or release some tension on the bullet , ya want enough to hold the bullet and let it slide back with a decent bit of effort...but no so much that it will allow the bullet to stick it too lil it just plop out. Anyhow stick it in long ,measure it

Fit the case on the bolt rim under the extractor and hand feed it in it it chambers

 

[Wolfdog91]

Gently pull it out and take that measurement. Do that a few times get an average an That's where your hitting the rifling .do with that what you may I like to BACK OFF the lands like .003


Now.... something I thought about was that when the gun actually runs...the rim of the round does go under the ejector till it's in the chamber and the bolt is slapping the back of the case .... As shown


some mabye ... Something might be different maybe I should try it ... So too that dummy plopped it in the chamber dropped the bolt release like I would if I was reloading a mag and

Yeaaahhh that's a bit different so.... I basically have two different deals now j can work off of and since the second is more like how stuff actually works...guess I do that ! So ended up running like 2.045, yeah that's supposed to be jam....but it ejected fine and easy with no marks ...so ... It can't be jammed idk..

So as far as powder I WAS going to use some of the magical H380 buuuut apparently that's only for like 55gr and up so we'll have to wait , BUT again I have the options between accurate 2460 and 2520 and since 2520 gave such good results last time just gonna run with that

And gonna go up a bit because this 20" barrel is loosing 300fos or so vs what the book says

 

[Wolfdog91]

and not a ton of case fill to start


Ok and or set up , same as before though I had to take the scope back off the .22 ARC to put it back on this girl

So other then forgetting to tighten up all my scope mount screws and having my 50yd bore site test jump all over the place don't really have any issues

 

[Wolfdog91]

O, I did dona lil test somon on here mention to me a while back . Basically I measured the CBTO of the last round in my mag before firing and then after I fired the first four to see if I got any bullet movement and would need a crimp

And it was the exact same ,I forgot to take a picture but it was 2.045 still.

But yeah other then that like I had to blow one round getting back on paper at 100yd but other then that this thing is a DREAM to shoot doesn't buck me out the scope and even though it has a 5lbs trigger ..it just don't feel like it idk how to explain it but
6 groups and all but one I think is sub MOA

Velocities are on the lowered side for a 250 but again ...20" barrel feel like I could stomp on it a lil harder and play with it some.more but this is bolt gun data and this is a gas gun so..... Not the safest thing to do....soooo guess the question is now ...which load ?

 

[Coyotefurharvester]

Sure looks like the vertical dispersion is reducing as charge weight increases (see this regularly). Perhaps a test with 35.2 and 35.4 to further reduce the vertical.