22-250 keyhole

[topclass2017]

I took my new Savage 12 in 22-250 (barrel twist measured at 1:11.75, or approx 1:12) out to the range for some load work. I started with factory loaded Federal 55g Nosler Ballistic Tips as a baseline to get on target at 100 yards, then switched to handloads, 52g Hornady ELD and 53g Hornady V-max, loaded at 2.350". As velocities increased (starting around 3500 fps and increasing to just over 3600 fps) the 52's began to keyhole big time, going through the target sideways (!) when they hit paper at all. No problem with the 53's at roughly the same velocity; my best 5-shot groups were in the 5/8" C-T-C range. My experience was the same using both Varget and 4064.

Any guidance? Should I be loading 52's slower? or even faster? Did I load too "short"? The Hornady manual calls for 2.350". I'm going to try 55g and 60g bullets as well...maybe 52 is too light?

 

[#40Fan]

Did you do any barrel break in? Cleaned it at all?

 

[Ledd Slinger]

This is the second Savage key-holing thread this week. Might have a trend here...

 

[topclass2017]

#40 Fan: Barrel break-in: 5 shots then cleaned; 5 more then cleaned; 10 shots then cleaned. Then began firing handloads

 

[270WinDude]

Since not many comments here, and I have no life.... So the ELD match and the Vmax should be darned close to the same bullet if I'm not mistaken... Which is strange the v-max isn't tumbling. Obviously simple fix is to just use the V-max. Have you measured what these bullets BTO length is in relation to your chamber? Are you just seating to the cannalure and if so is the brass in the middle of it, top of it or bottom?What are you using to seat the bullets? Is this new brass or FL sized, neck sized or what? I'm not personally familiar with the 22-250... in order to get up to that velocity where it BEGINS to keyhole what percentage of the case if filled with powder? I can run my 270win at 22-250 velocities with the 90gr varminters and somewhat 110 v-max but choose not to, so long as accuracy is there I'm happy with any bullet 2750-3200fps but that's just an arbitrary range that I picked.

 

[Sniper338]

Try a heavier bullet... those gr bullets your shooting perform best in a 14 twist. Try a 60-68 gr

 

[Steve morgan]

I took my new Savage 12 in 22-250 (barrel twist measured at 1:11.75, or approx 1:12) out to the range for some load work. I started with factory loaded Federal 55g Nosler Ballistic Tips as a baseline to get on target at 100 yards, then switched to handloads, 52g Hornady ELD and 53g Hornady V-max, loaded at 2.350". As velocities increased (starting around 3500 fps and increasing to just over 3600 fps) the 52's began to keyhole big time, going through the target sideways (!) when they hit paper at all. No problem with the 53's at roughly the same velocity; my best 5-shot groups were in the 5/8" C-T-C range. My experience was the same using both Varget and 4064.

Any guidance? Should I be loading 52's slower? or even faster? Did I load too "short"? The Hornady manual calls for 2.350". I'm going to try 55g and 60g bullets as well...maybe 52 is too light?

Never had a 52 to keyhole with a12 twist.have shot hundreds of them in 22-250 up to 3800/3900 fps

 

[BleedsBlue]

Any chance that the barrel is a faster twist than advertised?

 

[long40shot]

Your barrel may not have a fast enough twist to stabilize those ELDs. I can't find any data on recommended twist rate. It should though. Try some 50 v-max.

 

[SSL]

My 1-14" 22-250 puts 52-grain Amax/ELDM into tiny groups. Don't think twist is your issue but can't figure what it might be.

 

[topclass2017]

to one and all who have opined...

I measured the twist by using a piece of tape on a cleaning rod, so I am fairly confident that it is a 12 twist as advertised.

I have considered ramping up the speed of the 52's to see if they stabilize...or disintegrate. I've also considered the suggestion to either just use 53's and or go to a heavier bullet. I've got some 55 Nosler Ballistic Tips and 50 v-max loaded and ready to test. I'll be interested to see what happens with the 50's. Also some 60's but haven't loaded them yet. I'm thinking 55's and 60's may be the solution.

I'm using Lee dies to seat using Hornady manual specified COAL. I haven't measured how far off the lands that puts me yet -- that is a project for this coming weekend. I'm loading fired Winchester brass (not from this rifle) that was FL sized, trimmed, etc before loading. ID of case neck is .003" less than bullet diameter. I also have some new unfired brass to use, but only want to introduce one variable at a time.

 

[AckleymanII]

Topclass 2017, you need to buy a bore scope, lymans are on sale shipped at Brownell's for around $154.

XYZ barrels can be VERY rough inside, this is what you are dealing with now. Frequent cleaning with high quality bronze bristle bruses, good bore solvent, with frequent use of JB bore cleaner is needed to keep your barrel up and running.

Tooling marks can never be lapped out, must less minimized from any kind of break in process.

I had XYZ and some other factory barrels that needed to be cleaned every 35 rounds to maintain the level of accuracy that I needed, some in 7-9 rounds, others every 12-20 rounds.

If your bore exhibits a rough bore, frequent cleanings with very thorough cleanings will be necessary and a fact of life.

Fouling build up, usually carbon is what makes those bullets key hole.

https://www.brownells.com/gun-clean...ozen-pack-bronze-rifle-brushes-prod40081.aspx

https://www.brownells.com/gun-clean...d-2-oz--sku083065002-1160-4121.aspx?rrec=true

I really don't like being abrasive, I just help a lot of owners with their bores as they loose their minds trying to figure out what is destroying accuracy, key holes are always the result of these filthy bores.

Best wishes and good luck! Good cleaning brushes and JB will fix those key holes in a hurry.

This procedure has proven very effective on fouled bores:

run the rod through the bore without a brush on it
as the rod protrudes from the end of the barrel, screw on a new brush
saturate the brush with JB, it needs to look like a large snot ball
give the bore 10 strokes, then re apply the JB
give the bore a total of 60 strokes in this fashon
Throw the brush away
clean the bore of JB
Your bore should be down to bare metal
I use a Neil Jones cleaning rod or Lucas that centers the rod in the bore so that the rod is
not lapping the throat

new bronze bristle brushes are MUCH more effective than ISSO and Montana Extreme plastic brushes which I consider the best plastic brushes on the market.

Some barrels will smooth up, some NEVER do. Frequent cleanings maybe all that is needed to keep a barrel up and running. Your shooting needs will determine whether or not you will opt to spend money on a custom barrel.

Brownell's sells a 320 grit bore lapping solution for the worst of the worst cases, I use 180 grit sparingly with careful examination of the bore after only 5 strokes of 180 grit.

 

[hm1996]

Topclass 2017, you need to buy a bore scope, lymans are on sale shipped at Brownell's for around $154.

XYZ barrels can be VERY rough inside, this is what you are dealing with now. Frequent cleaning with high quality bronze bristle bruses, good bore solvent, with frequent use of JB bore cleaner is needed to keep your barrel up and running.

Tooling marks can never be lapped out, must less minimized from any kind of break in process.

I had XYZ and some other factory barrels that needed to be cleaned every 35 rounds to maintain the level of accuracy that I needed, some in 7-9 rounds, others every 12-20 rounds.

If your bore exhibits a rough bore, frequent cleanings with very thorough cleanings will be necessary and a fact of life.

Fouling build up, usually carbon is what makes those bullets key hole.

.

Lyman bore scope is very helpful determining best cleaning regimen for your bore. Without the bore scope we are shootin' in the dark. (pun intended) I've used a virtual chemistry set over the years, many on the recommendation of competitors at various rifle matches, and thought I was doing a good job. A friend brought over his new bore scope which revealed that many rifles I thought were clean had both copper and carbon fouling remaining.

Since I had cleaned my rifles faithfully, whether having been fired once or 300 rounds at a match, this came as quite a surprise. I ordered a Lyman scope and half a dozen additional solvents and set out to determine the most effective ones based on fact, not supposition. The old standby's obviously were not doing the job.

The bore scope allows you to see if/when you have to resort to abrasives, or which solvent will do the job with less wear and tear on your barrel. As Ackleyman pointed out, all barrels are not created equal, but even some of the XYZ barrels are capable of surprising accuracy......especially after looking inside of them. Obviously the factory barrels will require more TLC than premium barrels from any of the better known barrel makers.

Long story short, after inspecting with the scope, it was no wonder that one particular barrel was such a copper magnet. What was a surprise (to me) was that a white patch is no guarantee that all copper has been removed.

After cleaning w/conventional solvents (including occasionally with JB and Gold Medallion abrasives) and achieving the white patch. This was a factory barrel, after having been lapped. Wish I had taken some before lapping pics, but I didn't.

This picture is another factory barrel which has not been lapped. Both shoot moa, but the .308 (above) barely, and with only 3 (of dozens) of the bullets tried. The .338 WM below shoots .210 gr. NP's in the .5's w/boring regularity and sometimes better with NAB's & NBT's. Just goes to show you, some pretty rough bores shoot surprisingly well.

This barrel had been cleaned and put away after achieving the "white patch", using my old conventional cleaning procedure. Tool marks are quite visible and the large copper patch in left picture was a fairly large pit. Suspect this was a flaw in the barrel blank but cannot be sure as I was not original owner of this rifle.

After adding the new (to me) solvents I found Tactical Advantage (by Sharp Shoot R Precision, the same folks who make Wipeout) to be the most effective at removing both carbon and copper. Most of the other copper solvents are less effective on powder fouling. I apply TA to an IOSSO brush and scrub bore ten or twelve strokes, allow to sit (best overnight) and repeat if necessary. This removed the remaining copper and traces of carbon left after cleaning the old way.

"Some barrels will smooth up, some NEVER do. Frequent cleanings maybe all that is needed to keep a barrel up and running. Your shooting needs will determine whether or not you will opt to spend money on a custom barrel."

Since both of the above rifles are hunting rifles and have never fouled sufficiently to throw a flier, the bore scope reinforces my decision to clean, rather than replace them at this time.

Regards,
hm

 

[AckleymanII]

Great post, hm!

 

[Ned Ludd]

According to data listed Bryan Litz' book, "Ballistic Performance of Rifle Bullets", the minimum twist required for stability for the 53 gr V-MAX is 1:10.4"; for the 52 gr A-MAX, it is 1:10.9". I couldn't find any length or recommended twist rate data for the 52 gr ELD, but if it's as long or longer than either of those two similar weight Hornady bullets, your twist rate is likely not sufficient to stabilize them properly. When bullets go through the paper sideways, by far the most likely reason is insufficient barrel twist rate. Others may have gotten away shooting them through similar (or slower) twist rates if their muzzle velocity was significantly faster, or they were shooting them at significantly higher elevation than you. Nonetheless, your best bet is to contact Hornady directly and ask what their recommended twist rate is for that bullet before jumping through any other hoops to try and correct the issue.

 

[SSL]

That is what makes the issue so confusing. Generations of shooters had no problem with 55 to 60 grain bullets in 1-14" twist rifles since that was all that manufacturers made for 22-250s. It has only been fairly recently that faster twist barrels were available in production rifles in response to changing bullet designs. Every 22-250 I ever owned shot this weight range just fine with the exception of my current one...a 1970s Ruger #1B (from the era of very spotty barrel quality from Ruger's outsourcing of barrels). It just barely handles 55-grain bullets with marginal accuracy but puts 52-grain Amax or ELD-M bullets into .25 to .4" groups consistently at 3800+ fps. 50-grain and below produce indifferent groups.
My point is that the various studies are very helpful for 99% of applications, but there are always exceptions to the rule. Were I to rebarrel my rifle or buy a new one I would certainly opt for a faster twist in deference to the newer bullet designs on the market, but each rifle will always exhibit its own unique likes and dislikes.

 

[topclass2017]

July 7 RANGE UPDATE

As I had already loaded up 55g Nosler Ballistic Tips and 50g Hornady V-max's, I figured what the heck, shoot them and see what happens. Both bullets loaded over Varget and 4064. Based on my 52g ELD experience I had little hope for the 50's, but a glimmer of hope for the 55's.

To my complete and utter surprise, I found two nodes for the 55's with the better of the two under .4" CTC (5-shot group) at 100 yards, the "worse" one at .5" (also 5 shots). I wasn't even going to shoot the 50's after that, but did, and again found two nodes right at .5". Next up is to refine those 4 loads, adjusting seating depth and loading +/-.1g from the node. I'll also try 60g V-max as well.

So for whatever it's worth, my rifle doesn't like 52g ELD's or at least not the charges I tried. But as I found 4 good loads today, plus a couple acceptable 53's last week, I can do without finding the magic 52 answer.

I'll also call Hornady this next week and have a conversation with their tech guys. I've called them in the past and found tech support to be very helpful.

To say I am pleased is an understatement!

 

[SSL]

Very glad to hear you are making progress. It can be frustrating, but if it wasn't interesting and a challenge at times most of us would collect stamps!

 

[RGRobinett]

That is what makes the issue so confusing. Generations of shooters had no problem with 55 to 60 grain bullets in 1-14" twist rifles since that was all that manufacturers made for 22-250s. It has only been fairly recently that faster twist barrels were available in production rifles in response to changing bullet designs. Every 22-250 I ever owned shot this weight range just fine with the exception of my current one...a 1970s Ruger #1B (from the era of very spotty barrel quality from Ruger's outsourcing of barrels). It just barely handles 55-grain bullets with marginal accuracy but puts 52-grain Amax or ELD-M bullets into .25 to .4" groups consistently at 3800+ fps. 50-grain and below produce indifferent groups.
My point is that the various studies are very helpful for 99% of applications, but there are always exceptions to the rule. Were I to rebarrel my rifle or buy a new one I would certainly opt for a faster twist in deference to the newer bullet designs on the market, but each rifle will always exhibit its own unique likes and dislikes.

The issue (confusion) is because of the large variation in the length of bullets of equal weight - stability is MOSTLY about the length, not the weight, which, in practical application, is just along for the ride. The polymer tipped bullets are always longer than the 'old school' counter parts of the same weight, usually requiring fully 2" faster twist to attain stability equal to the bullets of yesteryear. Lengthening the bullet, without significantly increasing the specific gravity (the plastic tips a relatively LIGHT), increases the overturning moment. Sometimes, skirting along the ragged edge, we get lucky. RG

 

[long40shot]

The issue (confusion) is because of the large variation in the length of bullets of equal weight - stability is MOSTLY about the length, not the weight, which, in practical application, is just along for the ride. The polymer tipped bullets are always longer than the 'old school' counter parts of the same weight, usually requiring fully 2" faster twist to attain stability equal to the bullets of yesteryear. Lengthening the bullet, without significantly increasing the specific gravity (the plastic tips a relatively LIGHT), increases the overturning moment. Sometime, skirting along the ragged edge, we get lucky. RG

This is spot on. I had the exact results. 55grn v-maxs shoot decent in my new 1-14 barrel, but 55 Sierra Blitzkings drive tracks.