Is this what I think it is?

[Mark Terry]

I'd posted earlier about a Ruger #1V in .220 Swift I was bringing back out in the daylight. I resolved the scope mounting issue with the help of Ruger who provided a block for the middle mounting holes and I'm using a substitute scope while I wait on a better scope.

I loaded up a few rounds using Hornady 50 grain V-Max bullets at less than maximum velocities. Specifically, I loaded IMR 4895 at 37.7 grains in Hornady brass using WLR primers. Average velocity was 3,672 fps. I also loaded H380, VVV N150, and IMR 4064 powders but that's not the problem at this point.

Take a look at the picture below. It appears that the bullets are tumbling or yawing or in any event passing through the target close to sideways.



The velocity seems reasonable compared to the manuals and it doesn't appear the bullets are coming apart.

Anyone have any idea why this is happening?

I will load and shoot some Speer 55 gran softpoint Varmint and Sierra MatchKing 52 grain later today if time permits.

Thanks

[bigbrowndog]

Many things can cause a bullet to tumble, insufficient velocity to provide spin, too slow of rate of twist, too long of bullet for rate of twist, something impeding the bullet exit at the muzzle, or something impeding the bullet path after exiting the barrel, a dirty barrel can cause it by destroying the bullet jacket as it passes thru and creating a non concentric projectile or simply bad bullets.

Easiest things first, check your crown for a ding, clean your barrel, check your rate of twist, try different bullets.

Trapr

[mod70]

Yes, 3,700 is pretty fast for a 50 grain like that in the swift. I have done the same thing in mine with different 55's even blowing some up on the way. The very best bullet I ever used in my swift was the Hornady 53 grain hollow point match. The swift velocity blows them up on woodchucks no problem with excellant accuracy way out there.I used to push them at 4,000 measured.
John Roberts

[Mark Terry]

Well, neither the Speer or Sierra bullets made anything but nice round holes making me suspect the Hornady bullet may not be well suited for the higher velocities. The Hornady is what I shoot in .223 and it performs fabulously (at the lower velocities). Then again, I could load the Swift down but I can't figure out why I would.

I appreciate the input. I was limiting myself to the bullets marketed as "varmint" bullets but any bullet approaching 4,000 fps is bound to do the trick on any varmint. I used to shoot Sierra MatchKings for groundhogs and crows "back in the day" before the advent of varmint specific bullets.

This Ruger is supposed to have a 1:14 twist and I'd think that might be slow for shorter bullets but I'm short on knowledge here.

The next step is to source some decent optics and start over again. Any recommendations for a modern varmint scope?

Thanks,

[nolongcolt]

I don't know anything about the Swift but the twist works this way generally. Long, heavy bullets like a quick or steep twist. Shorter, lighter bullets like a slower twist. Its actually more about the length or bearing surface of the bullet than the weight itself. If this rifle shoots other bullets without tipping and all else being equal, I would just avoid that particular bullet.

[lange1]

I've heard of this with the Swift, and if I'm not mistaken, with some 22-250s and the V-max loaded to less than upper velocities. Both have a slower twist for a 22. Seems like the 3,670 fps is not too slow, max is another 300 or so, but if it was me, I'd say speed 'em up a bit and see if they stabilize. Maybe that 10% makes a big difference in stability. Otherwise, like was said above, switch bullets.

I have a pretty sweet Nikon 6x24 AO that right now sits on my 257 Wby that I love, it has very fine crosshairs, and super repeatable adjustments. The new ones have the objective adjustment at the turret, I haven't tried one of those. I'd get another Nikon if I needed, usually I am partial to Leupold, I've broken several other brands, but the Nikon is really clear and lets lots of light in. I could hit magpies at 500 with it on my Winchester Coyote in 22-250 all day long.

[tek4260]

I'd look at the crown before I touched anything else. That 50gr bullet is shorter than the "normal" 55ish gr bullets that most shoot, so I wouldn't think the twist is too slow.

I've read somewhere about using White-Out to paint the crown. Then you can look at the marks from the exiting gas to see if it is "even" so to speak. If there is a ding bad enough to make them tumble to that extent, I'd just about bet you could see it with your naked eye.

[bradshaw]

Mark Terry.... keyholes, to be sure, all three with close to the same timing. For this reason, I doubt barrel harmonics are at play, although it is something to keep in mind, especially if barrel-to-receiver mount is suspect.

Twist
Takes a radical rise in velocity to overcome a slow-for-bullet twist. Try a flatbase bullet. If the flatbase keyholes, look at groove diameter.

Groove diameter
Oversize groove diameter degrades accuracy, without necessarily inducing noticeable yaw. Some bullets are more sensitive to an overside groove than others.

Bore uniformity
First stop: a flatbase bullet. Bore uniformity is a must for accuracy; the more sensitive the bullet and load, the more important bore uniformity becomes.

Leade
The chamber leade, or transition ramp between chamber and lands, must be smooth and gradual for accuracy. A rough or abrupt leade kills accuracy all by itself in a rifle. However, the first issue is those keyholing bullets, and I doubt leade is a factor.

Crown
A rough muzzle crown may throw fliers; don't know whether it would induce keyhole.

You may want a another scope but... as you know... a keyholing bullet has no idea what sort of sight is on the rifle.
David Bradshaw

[dmize]

I will double check but I am pretty sure I have pushed that bullet at near if not over 4,000 in my 22-250 with sub MOA groups at 300 yards.
Saying this because I don't think you are stressing that bullet.

[Mark Terry]

David,

You mean to tell me the scope isn't causing it? Seriously, I appreciate the advice from everyone.

When I used to shoot this one regularly, I was always proud that it shot very good and generally better than my buddies bolt actions. Which is why it's a little confounding now.

I remember reading Mr. Barsness about how he was able to salvage 220 Swifts that had been "shot out" by cleaning the barrel to remove residues.

What's our favorite barrel cleaning juice and regimen?

I looked specifically to see if I saw anything about limiting velocity on this bullet and didn't find anything and I'd tend to think it ought to be good to whatever you could do in a 220 or 22-250.

The crown is recessed and looks perfect. I will try the white out trick to see if there's anything to be learned.

Thanks

[nolongcolt]

Regarding cleaning, I use old No 9 for powder fouling and copper too if it isn't too deep. If copper is hard to get out I use Barnes CR10, and get down to bare metal. Its amazing how many guys shoot really dirty rifles and wonder why they quit shooting. Not saying you, but I have seen guys here and elsewhere claim they never clean a bore which is like saying I never change oil in my car, it doesn't need it!

[mod70]

Mark Terry when I used to shoot the swift I cleaned every 20 rounds no more than 25 as the accuracy whould be gone. I used quicksilver engine cleaner spray it in let it set a bit and patch out accuracy would be right back. I used dupont 4064. Once in a while I would use some jb in the throat. Just looked the bullet up Hornady says to 4200.
John Roberts

[lange1]

Agreed, not the scope. You could put the $5.00 Walmart Tasco scope on it and it wouldn't make the bullets keyhole. I just thought you wanted a sweet new scope. But I am fairly confident that bullet needs to be run faster to stabilize.

[Mark Terry]

I appreciate the insight. It would seem to make some sense that running up close to 4,000 fps might make fouling more of an issue. Keep in mind this rifle hasn't been shot in years. I will make sure fouling isn't a problem.

John - I have loaded some 4064 and will eventually get to those. I used to have good luck with it in a .22-250.

I've used this bullet (Hornady V-Max, 50 grain) in a Remington 700 .223 with outstanding results at 3,164 fps (1:12 twist). Correct me if I'm wrong but the spin rate 3,164 fps at 1:12 is pretty much the same as 3,672 fps with 1:14.

Yes, lange1, I want a sweet new scope. This all started because of old eyes and an old scope.

Just don't tell the wife the scope didn't cause the keyholing.

[bradshaw]

Mark.... that the rifle shot great, with accuracy now falling off, sounds like fouling. I'd try John Roberts' suggestion of swabbing with Mercury Outboard Quicksilver, an aerosol white foaming chemical which instantly attacks carbon. Also sold by Chrysler and GM, I believe. Kroil, a strong penetrant, works on carbon but not nearly as fast as Quicksilver. Eliminator bore solvent attacks jacket fouling and seems to cut carbon fouling. Butch's Bore Shine finds favor with a number of accuracy shooters.

Some of these post-modern bore solvents are said to attack steel if left in more than five or ten minutes, while others claim to be harmless. My take: only Hoppe's Number 9 deserves to be left in the bore indefinitely. Hoppe's is slow as molasses in January at going after serious fouling.

Having swabbed the bore in good shape, bag it with a proven load. If it shoots dead nuts, forget the Keyhole Special.

If a proven load goes all to jelly, clean once again with powerful solvent. Follow with a few fire lap bullets. Clean and shoot again with proven load.

If accuracy is great with flatbase bullets, yet lousy with boattails, stick with flatbase.

An old, proven load is your benchmark.
David Bradshaw