Form 1 keyholing with full power loads

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ChimeraPrecision
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Form 1 keyholing with full power loads

Post by ChimeraPrecision »

So, my form 1 22 can works like a charm, unless I am using full power loads in my ruger 22/45 lite. It keyholes all day with full power federal hollow points.

It never ever keyholes with Anguilla subs, or CCI standard. Drives tacks

Has anyone else noticed a phenomenon like this?
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Re: Form 1 keyholing with full power loads

Post by Bendersquint »

ChimeraPrecision wrote:So, my form 1 22 can works like a charm, unless I am using full power loads in my ruger 22/45 lite. It keyholes all day with full power federal hollow points.

It never ever keyholes with Anguilla subs, or CCI standard. Drives tacks

Has anyone else noticed a phenomenon like this?
What is your bore diameter?

It may be too tight for the inaccurate Federal ammo.
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

Bore is .279-.280

Also I can hear the projectile going supersonic. So the pressure wave may induce some instability
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Re: Form 1 keyholing with full power loads

Post by Bendersquint »

ChimeraPrecision wrote:Bore is .279-.280

Also I can hear the projectile going supersonic. So the pressure wave may induce some instability
That bore is enough that it shouldn't be posing an issue.

No, the pressure wave wouldn't be causing instability, if that was the case no supersonic round would be accurate.

Something is off with the barrel, check the crown and the bore and scrub it down good.

My P22 did that after about 15,000 rounds because I wore the rifling off. Replaced the barrel and its fine
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

Bendersquint wrote:
ChimeraPrecision wrote:Bore is .279-.280

Also I can hear the projectile going supersonic. So the pressure wave may induce some instability
That bore is enough that it shouldn't be posing an issue.

No, the pressure wave wouldn't be causing instability, if that was the case no supersonic round would be accurate.

Something is off with the barrel, check the crown and the bore and scrub it down good.

My P22 did that after about 15,000 rounds because I wore the rifling off. Replaced the barrel and its fine
Would your firearm stabilize subs ok? This gun is almost new. Maybe 1k down the pipe
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Re: Form 1 keyholing with full power loads

Post by Bendersquint »

ChimeraPrecision wrote:
Bendersquint wrote:
ChimeraPrecision wrote:Bore is .279-.280

Also I can hear the projectile going supersonic. So the pressure wave may induce some instability
That bore is enough that it shouldn't be posing an issue.

No, the pressure wave wouldn't be causing instability, if that was the case no supersonic round would be accurate.

Something is off with the barrel, check the crown and the bore and scrub it down good.

My P22 did that after about 15,000 rounds because I wore the rifling off. Replaced the barrel and its fine
Would your firearm stabilize subs ok? This gun is almost new. Maybe 1k down the pipe
Yup no issues with subs, only the supers would zing down range.
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Re: Form 1 keyholing with full power loads

Post by Pman5KMO »

Could it possibly be that the pistol barrel is not long enough to get the projectile up to a sufficient velocity, that it is decelerating into transonic ranges 10m in front of the barrel destabilizing the projectile? I know chronograph data would pin point if this is the issue. I would also test without suppressor to see if it works fine or not.
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

Pman5KMO wrote:Could it possibly be that the pistol barrel is not long enough to get the projectile up to a sufficient velocity, that it is decelerating into transonic ranges 10m in front of the barrel destabilizing the projectile? I know chronograph data would pin point if this is the issue. I would also test without suppressor to see if it works fine or not.
Those are my thoughts. The gun shoots great without the can, using bull pack HV ammo
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Re: Form 1 keyholing with full power loads

Post by SRM »

I'm gonna be watchin this thread as this is strange. All my rimfire firearms take whatever I give'em. Hell, my sbr'ed 10/22 with a 4 3/4" factory barrel shoots the sss just fine. This is all suppressed too.

Am I understanding this correctly?
The pistol shoots fine without can with HV ammo and kee holes with can same ammo, yet shoots subs with can just fine.
Is this correct?

I do not think its the velocity because if it shoots without the suppressor it should shoot with it..... It has to be the can. Would you mind showing the cans guts. It will help 'us' help you!
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

SRM wrote:I'm gonna be watchin this thread as this is strange. All my rimfire firearms take whatever I give'em. Hell, my sbr'ed 10/22 with a 4 3/4" factory barrel shoots the sss just fine. This is all suppressed too.

Am I understanding this correctly?
The pistol shoots fine without can with HV ammo and kee holes with can same ammo, yet shoots subs with can just fine.
Is this correct?

I do not think its the velocity because if it shoots without the suppressor it should shoot with it..... It has to be the can. Would you mind showing the cans guts. It will help 'us' help you!
You are understanding correctly.

viewtopic.php?f=10&t=98129

Baffles are posted in this thread.

I will try and get to the range and get pictures of what is happening
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Re: Form 1 keyholing with full power loads

Post by SRM »

Its the blast baffle. The hole.

The blast is coming back on the bullet before it goes through the second baffle. This is why subs are good.
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Re: Form 1 keyholing with full power loads

Post by SRM »

Get rid of that blast baffle and make another spacer for the second baffle. Um, send to an 02/07 and have them do the said. :mrgreen:
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

SRM wrote:Its the blast baffle. The hole.

The blast is coming back on the bullet before it goes through the second baffle. This is why subs are good.
But, the rifle with exact same ammo doesn't keyhole
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Re: Form 1 keyholing with full power loads

Post by pneumagger »

Does the silencer when used on several different hosts exhibit the same behavior? WHat about using a different .22LR silencer on the problem-gun... same results?
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

pneumagger wrote:Does the silencer when used on several different hosts exhibit the same behavior? WHat about using a different .22LR silencer on the problem-gun... same results?
Sr22 did it occasionally, if I use CCI standards all is well.

I am going to try and align the baffles better, and take out the blast baffle to see possible behavior change
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

UPDATE

Today I took my rifle, pistol, and can to the range and did some tests with CCI standard ammo.

Pistol: with blast baffle in -- keyhole every round
Without blast baffle -- not one keyhole

Rifle: with blast baffle in -- no keyholes observed
Without blast baffle -- no keyholes observed



Action items: I am going to punch another hole in the blast baffle opposite the one already there and see if this helps

If it doesn't, I will reluctantly find an 07/02 to make me a spacer and remove the blast baffle
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Re: Form 1 keyholing with full power loads

Post by Bendersquint »

ChimeraPrecision wrote:UPDATE

Today I took my rifle, pistol, and can to the range and did some tests with CCI standard ammo.

Pistol: with blast baffle in -- keyhole every round
Without blast baffle -- not one keyhole

Rifle: with blast baffle in -- no keyholes observed
Without blast baffle -- no keyholes observed



Action items: I am going to punch another hole in the blast baffle opposite the one already there and see if this helps

If it doesn't, I will reluctantly find an 07/02 to make me a spacer and remove the blast baffle
We have spoken before, we can get you taken care of if needs be........personally I wouldn't hesitate about not using that "blast baffle" it inefficient to the design.
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Re: Form 1 keyholing with full power loads

Post by Fulmen »

Weird, could be marginal clearance as well. The marginal clearance could produce an asymmetrical force on the bullet, higher pressures would amplify the effect. With asymmetrical baffles it is recommended to have a fairly large symmetrical blast chamber to reduce the effect, I think I produced the same effect om my 222-build as I noticed a slight reduction in accuracy with the can. Don't have the numbers at hand but IIRC I started with 6,5mm bore and opened to 7. Final word isn't in yet, but it seems I fixed the issue with undetectable decrease in suppression.
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Re: Form 1 keyholing with full power loads

Post by SRM »

interesting situation indeed.

I bet it would work without the hole in the baffle. weld it up.
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Re: Form 1 keyholing with full power loads

Post by ChimeraPrecision »

SRM wrote:interesting situation indeed.

I bet it would work without the hole in the baffle. weld it up.
I will try this first. Excellent suggestion

And B, if need be, I will get with you
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