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Need help with this over pressure issue


Knucky McPee

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I shot my short stroked vaqueros this weekend for the first time and every stage I would get a loud bang like a double feed on my loads on each revolver. Deb and I are using the same ammo and it never happened to her at all. Also it never happened on my rifle. My load is 105 gr bullet with 3.2 gr of trail boss in 357 cartridges. Take a look at the sunburst on each pistols cylinder. This is really weird and I am stumped.  Also I use a Dillon RL1100 with a powder check which I not only listen to but watch each round. Any ideas.

Also using Remington primers and also was told it happened a couple of times on my rifle. 

Thanks Knucky

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15 minutes ago, Goody, SASS #26190 said:

What did the primer look like in the fired case for the rounds that sounded heavy? I assume the heavy charge sounding rounds were the ones with starred chambers?

Thanks Goody. I was just going out to look at this. I also loaded these rounds with Remington primers. I will let you know what I find out. Thanks

Knucky

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Holy shith Batman!  It has to be a significant issue to cut into the chamber mouth like that.  I’d bring it to a competent smith before using it again.  Be safe  

 

EDIT - I was just thinking about this.  Have you taken caliper measurements of the chamber length and bore diameter compared to the other chambers?

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To determine the issue, you have to look at the cases that caused the blow back.  We’re there no splits or broken webs on the cases? Bottom line, no cases ... clean the blow back off - look at the area with a 20X magnifying glass - no sign of a a cracked cylinder ... just an Unsolved Issue

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7 minutes ago, John Boy said:

To determine the issue, you have to look at the cases that caused the blow back.  We’re there no splits or broken webs on the cases? Bottom line, no cases ... clean the blow back off - look at the area with a 20X magnifying glass - no sign of a a cracked cylinder ... just an Unsolved Issue

 

Question - if there was a problem with the cases don’t you think it’s odd that it’s only on one chamber on different cylinders?

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I just looked at all the brass from this weekends match.  All 240.  Problem is I had already cleaned them in my wet tumbler. There were no split cases nor were there any signs of over pressure on the primers. I should have looked at this after the stage. Good lesson learned.  

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I am pretty sure what you are seeing is lead being shaved off the bullet due to mis-alignment between the barrel and the cylinder. 

 

Check that the cylinder is properly indexed and lined up with the barrel. You shouldn't be able to rotate the cylinder in either direction if the bolt is in the locking notch on the cylinder.

 

You will need to do this by cocking the pistol the same as you do during a match.

 

 

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One more thing to mention. I normally shoot black powder (777) and never ounce experienced this. This is the first time for me shooting smokeless with these revolvers. 

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Anyway the cylinders could have been swapped between guns? That number scratched on the end of the cylinder should be the last 3 digits of the serial number for each gun.

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32 minutes ago, Knucky McPolack said:

One more thing to mention. I normally shoot black powder (777) and never ounce experienced this. This is the first time for me shooting smokeless with these revolvers. 

 

The key phrase in your original post.

 

2 hours ago, Knucky McPolack said:

I shot my short stroked vaqueros this weekend for the first time

 

That silver color on the face of your cylinder is lead. 

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Knucky edited his post above to say that some folks reported him having some louder rifle rounds as well.  While there certainly may be indexing problems, it may well  be an ammo issue since it happens in 3 guns.  But then why did not any happen in the wife's guns?  Mysterious.

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As a commercial reloader for too many years, I will say I did not like the performance of Trail Boss.

In low velocity rounds the ignition was not consistent.

Once the velocity was up to 750’/sec the round became more consistent.

 

I choose to use other powders for my customers.

 

Now, what I see may be a light load round.

When fired the primer pressure build up causes the bullet to jump in to the forcing cone but not move through it to the barrel.

Then the powder ignites and the pressure jump up very high to push the bullet which is obstructing the barrel at the forcing cone.

The result is high pressure and extreme heat on the base of the bullet allowing for lead to spreads out the cylinder gap before the bullet clears the gap totally.

Check the velocity.

If it is low then bump up the powder charge to get the bullet to move through the forcing and not stop.

===============

I would say there is a cylinder to forcing cone alignment issue if it is happening in the same chamber or if it is happening in two different cylinders.

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51 minutes ago, Cliff Hanger #3720LR said:

As a commercial reloader for too many years, I will say I did not like the performance of Trail Boss.

 

In low velocity rounds the ignition was not consistent.

Once the velocity was up to 750’/sec the round became more consistent.

 

 

I choose to use other powders for my customers.

 

 

Now, what I see may be a light load round.

When fired the primer pressure build up causes the bullet to jump in to the forcing cone but not move through it to the barrel.

Then the powder ignites and the pressure jump up very high to push the bullet which is obstructing the barrel at the forcing cone.

The result is high pressure and extreme heat on the base of the bullet allowing for lead to spreads out the cylinder gap before the bullet clears the gap totally.

Check the velocity.

If it is low then bump up the powder charge to get the bullet to move through the forcing and not stop.

===============

I would say there is a cylinder to forcing cone alignment issue if it is happening in the same chamber or if it is happening in two different cylinders.

This is exactly what happened because when I experienced the over pressure round I had a flash out the sides of the gun. It was like shooting a flint lock. Click bang. Also my rounds were inconsistent. Had some mouse fart rounds. I just got back from the range after loading some rounds with 4.4 gr 700x with 125 gr fnrp.  I'm out of titewad. Those all were good and consistent. The mysterious part is why my wife never had an issue. Luck of the draw I guess.   Good info thanks Cliff Hanger

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59 minutes ago, Cliff Hanger #3720LR said:

 

Check the velocity.

If it is low then bump up the powder charge to get the bullet to move through the forcing and not stop.

===============

I would say there is a cylinder to forcing cone alignment issue if it is happening in the same chamber or if it is happening in two different cylinders.

What Cliff said, it takes more power to push a light bullet. Try some factory rounds to see if it happens there. Years ago at  an  ER shooting school he had us shooting paper to find out where we actually hitting, said most guns have one cylinder that is just a little off, find it, mark it so you never load it.  Good Luck:) Never mind I type to slow, glad you got figured out;)

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1 hour ago, Runamuck, SASS #49216L said:

Check that brass from last weekend to see if any have any off-center primer strikes. Sounds like a indexing problem.

 

Howdy Muck. I checked the primers of the rounds I just fired with 700x and they are striking in the middle. Thanks

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5 minutes ago, Jefro, SASS#69420 said:

What Cliff said, it takes more power to push a light bullet. Try some factory rounds to see if it happens there. Years ago at  an  ER shooting school he had us shooting paper to find out where we actually hitting, said most guns have one cylinder that is just a little off, find it, mark it so you never load it.  Good Luck:) Never mind I type to slow, glad you got figured out;)

Thanks Jefro. I really need to get me a chronograph so I know my velocities. If this happens again I will be sure to mark the cylinder and inspect the primer immediately at the unload table. Thanks

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2 hours ago, Goody, SASS #26190 said:

Anyway the cylinders could have been swapped between guns? That number scratched on the end of the cylinder should be the last 3 digits of the serial number for each gun.

That was the very first thing I checked. Was wondering if I had a Knuckyism and put the wrong cylinders in the guns. 

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1 hour ago, Cliff Hanger #3720LR said:

As a commercial reloader for too many years, I will say I did not like the performance of Trail Boss.

 

In low velocity rounds the ignition was not consistent.

Once the velocity was up to 750’/sec the round became more consistent.

 

 

I choose to use other powders for my customers.

 

 

Now, what I see may be a light load round.

When fired the primer pressure build up causes the bullet to jump in to the forcing cone but not move through it to the barrel.

Then the powder ignites and the pressure jump up very high to push the bullet which is obstructing the barrel at the forcing cone.

The result is high pressure and extreme heat on the base of the bullet allowing for lead to spreads out the cylinder gap before the bullet clears the gap totally.

Check the velocity.

If it is low then bump up the powder charge to get the bullet to move through the forcing and not stop.

===============

I would say there is a cylinder to forcing cone alignment issue if it is happening in the same chamber or if it is happening in two different cylinders.

Cliff Hanger, I just ordered a chronograph. been wanting to get one. Is there a formal for obtaining pressure using the velocity and weight of the bullet. Or how do you obtain the pressure. Thanks

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How about looking closely at the barrel forcing cone, right at the breech end of the barrel.   Look for lots of lead fouling, or even a crack in the barrel.   

 

And, BTW, how COLD was your ammo at the time you had the problem?  Cool or cold morning?   Ammo left in the weather overnight, possibly?   Cold weather makes inconsistent loads even more pronounced for most powders, including TB.

 

I'd agree strongly with Cliff Hanger.  This was likely a low-powder detonation due to the bullet starting in the forcing cone just due to primer, then a delayed ignition of the powder with bullet firmly stuck in the barrel/cylinder gap.

 

Solution to this DANGEROUS situation is to LOAD NO LESS THAN MINIMUM RECOMMENDED POWDER CHARGE WITH TRAIL BOSS POWDER!!

 

TB does not really give a consistent load (even for Cowboy) until you get to the midway point of published loading data ranges.  If you want really light loads, use 700-X, Red Dot, Clays or other powder that is proven to work well in light loads.  

 

Good luck, GJ

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Without the BS it is pretty clear that you had an overcharge.  Particularly since you had inconsistent loads prior.  You should check your powder measure by weighing a number of loads on a scale, maybe 10 to 20 rounds.  Also run all of the powder through a sieve to make sure that there are no lumps or foreign matter in the powder.  And clean the powder measure.  You’ve definitely got a serious problem and need to find out what it is before someone gets hurt.

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Due to the "fluffiness" of Trail Boss, some powder measures will not let it flow decently without giving it extra time. It is bad for "bridging", I have seen it with both Lee and Dillon powder measures. You could have had a light charge, then heavier on the next round.

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"Cliff Hanger, I just ordered a chronograph. been wanting to get one. Is there a formal for obtaining pressure using the velocity and weight of the bullet. Or how do you obtain the pressure. Thanks"

=====================

Sorry to say, with out the correct equipment checking the actual pressure is going to be almost impossible.

Even more to that, you want to test a revolver that has a cylinder gap that the pressure will bne release at.

http://closefocusresearch.com/calculating-barrel-pressure-and-projectile-velocity-gun-systems

 

For revolvers you want a velocity that will push the bullet through the forcing cone.

Slower burning powder, raise the velocity, heavier bullets to slow the case release tension.

 

Over 18 years of relaoding commercially and help from a gun smith who tesed bullets and powder at the range once a week, I listened to his comments.

He said there was a point when lower the velocity that burn rate is no longer consistant, velocity is erratic and accuracy would wonder over the target.

He showed me examples in several calibers from 32-2- to 45-90.

 

On pistol calibers, velocities under 650'/sec where not useful.

I set my commercial reloading to get as close to 720'/sec as I could because it show the best accuracy and no bullets stuck in barrels.

Also showed the least leading on cylinder face.

 

Also he showed me that in choosing bullet weight, you can get too light and the bullets will not preform.

Some will tumble at 30' from the barrel and others would not hold on to the case enough to build up pressure before moving.

 

The recoil difference from 105gr to 125gr Is not noticable.

Except in accuracy and velocity averages.

 

Some will argue that the lighter bullets are better but when shooting 10' to 20' it really doesn't matter.

Try shooting 60' and check grouping.

============

I shoot 45 colt in Ruger Vaqueros.

I choose 200gr bullets to get enough recoil to bring the hammer back to my thumb instead having to reach forward to the ahmmer.

This gave me faster shot to shot recovery.
 

My many years of reloading for others shows the 125gr TC was the most popular bullet used in 38 cal by far.

One more item of interest.

What I loaded for others is exactly what I personally shoot. (720'/sec in all pistol calibers.

 

Rifle calibers is a little different and for another day.

A tease....1370'/sec. for the larger calibers. 38-55, 40-60, 45-70.

1370'/sec just happens to be a full case of Goex FFg, 1/8" compressed with primer box card.

I tested smokeless powder until I got the same velocity of 1370'/sec.

 

 

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On top of all of the above, your shooting Rugers.  Rugers are notorious for undersize Cylinder Throats.  You need to check your throats.  Drop a lead bullet you know to be sized .358 in the chambers.  You should be able to push the bullet thru the throat with light pencil tap.  If you have to "drive" it through the throats are too tight and need reamed.  Tight throats will just exacerbate "Premature Shot Start."

 

On a personal note, I don't like Trail Boss for anything.  When shooting that fad heathen Smokeless stuff, I have preference for TightGroup.

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First of Ruger uses a 5 Degree Lead ( forcing Cone ) that is very short and often not cut totally straight , I re-cut a number to a longer 11 degrees in my shop every year.  I also reface the breach end of barrels to increase cylinder Gap for trouble free use with Holy Black ...  

You would be surprised how many revolvers are not on face ( Square  between cylinder and Barrel ) and this happens with all brands ...

 

Jabez Cowboy

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18 hours ago, Knucky McPolack said:

I shot my short stroked vaqueros this weekend for the first time and every stage I would get a loud bang like a double feed on my loads on each revolver. Deb and I are using the same ammo and it never happened to her at all. Also it never happened on my rifle. My load is 105 gr bullet with 3.2 gr of trail boss in 357 cartridges. Take a look at the sunburst on each pistols cylinder. This is really weird and I am stumped.  Also I use a Dillon RL1100 with a powder check which I not only listen to but watch each round. Any ideas.

Also using Remington primers and also was told it happened a couple of times on my rifle

Thanks Knucky

 

18 hours ago, Knucky McPolack said:

 

Posted 13 hours ago. Sedalia Dave

Missed the load data info.

 

Per Hodgdon the minimum charge for a 105 gr bullet in a .357 case is 3.5 grains.

 

 

Following the powder manufacturer's load recommendations could solve your problem and prevent future injuries from fellow cowpokes.

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4 hours ago, Matthew Duncan said:

 

 

Following the powder manufacturer's load recommendations could solve your problem and prevent future injuries from fellow cowpokes.

Yup. I don't know how I came up with the load I did. I usually load a little heavier on the light side of the recommendations. See too many pards have squibs because of this. I got a lot of bullets to take apart. 

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48 minutes ago, Warden Callaway said:

Have you taken this up with Ruger?  I bet they cut the chambers in some automated gang operation. Maybe one chamber didn't get a final cut?

 

Evidently you didn't read the posts where the OP was loading less then the manufacturer's minimum powder loads nor the post where problem was occurring in pistol AND rifle?

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