Pressure issues, need some help

[mgunderson]

Each cartridge that has small and large primer options, has its own adjustment for adjusting data. Small primer data to large primer always is a reduction in propellant.

You understated the adjustment and didn't get hurt. Count yourself lucky. We don't always get this lucky. Some cartridges are closer to 1/2 grain, but the internet doesn't get this stuff right very often.

The internet comments do not have the safety check that published data does. Do you trust us enough to stake your face on it?

I appreciate the post and hope we help others avoid the issues many of us ( me included) have experienced along the way.

 

[DLT]

Each cartridge that has small and large primer options, has its own adjustment for adjusting data. Small primer data to large primer always is a reduction in propellant.

You understated the adjustment and didn't get hurt. Count yourself lucky. We don't always get this lucky. Some cartridges are closer to 1/2 grain, but the internet doesn't get this stuff right very often.

The internet comments do not have the safety check that published data does. Do you trust us enough to stake your face on it?

I appreciate the post and hope we help others avoid the issues many of us ( me included) have experienced along the way.

I’m learning. I just assumed all but 3 grains below their max would have been safe

 

[big5ifty]

I’m learning. I just assumed all but 3 grains below their max would have been safe

A better approach to have is to start at the minimum and work up, provided all else is as per the load data.

Out of curiosity, how did you get that expanded case out of the chamber ?

 

[DLT]

A better approach to have is to start at the minimum and work up, provided all else is as per the load data.

Out of curiosity, how did you get that expanded case out of the chamber ?

I have an old cleaning rod I went in through the muzzle a few love taps with a hammer and it came right out. I figured it was welded to the chamber to be honest.

 

[DLT]

Good catch !!!!
Thats probably the main culprit here

I don’t think so.

*Update* today I sent my headspace with the go gauge. After it was set I used 1 piece of scotch tape (.0015- .002) on the back of the gauge and my bolt won’t close so I’m good there. I might have turned the barrel 1/16 of a turn from where it was. Anyway new lapua small rifle brass I started today down another grain so 37.5gr of n160 with a cci 450 primer and smoked and blew out the primer on the first shot at 3058fps. I came down another 1.5gr to 36.0 those 3 rounds stamped the brass hard with an average of 2967. Still over vv max velocity while being 5 grains below their max charge and 1gr below their starting charge. I give up on n160 not worth it to me. I Loaded 3 with 39.0gr of h4350 and had no pressure of any kind 2974 avg fps.

Not 1 thing has added up other than this power is hot as piss in this rifle. No explanation

 

[DShortt]

Maybe you got some old stock powder? I've heard of powder becoming unstable over time, particularly if the storage conditions included high temperatures.
I'd walk away and stick with what you know works.

 

[DShortt]

10 in shifting winds.

 

[searcher]

A better approach to have is to start at the minimum and work up, provided all else is as per the load data.

Out of curiosity, how did you get that expanded case out of the chamber ?

I agree with big5ifty here. Everyone -myself included - likes to take calculated short cuts when we can. This is clearly a case where the powder manufacturers and manual makers have done this "calculating" for us. On the side of extreme safety, we can either assume we know more than them or not, as to where we start on a powder charge. If you start right off with an over-pressure load - you don't know how much to reduce the load. The manuals often also won't tell you how much to reduce a load - as they assume you worked up - and would have seen at what level you had no high pressure - and where you did. When I work up a new load, I do it over a chrono and I only load two rounds at the bottom, then another two, and so on, until I'm getting the velocity range I want to be in with a particular powder - then I do larger groups, with finer incremental changes. So maybe I waste ten rounds and a few more minutes for the barrel to cool. Worth saving what is left of my looks and life. I say this for all beginning reloaders. There truly is inherent danger in what we do, and big mistakes don't happen until they do. If the manuals are followed, it is truly rare for serious problems to occur. Some manuals are much more comprehensive than others and much more explanatory. I personally think the Berger would be one of the top choices for someone starting out. I think if I had been in your situation - after doing this for a "while", I'd have dropped the load to a starting load and worked back up, with the knowledge that part of the problem for the primer escaping the cartridge may have been due to brass that had not fireformed to the longer chamber, creating an "unsupported" cartridge condition by the bolt. The second firing at a lower pressure would likely see all problems disappear.

For bolt damage to occur for your high-pressure rounds, you would likely have had to incur something more than a blown primer to damage the bolt, other than flame cutting from the hot gasses being blown onto your bolt face. I'd still look for a cracked bolt lug or any abnormality in the surfaces of the action - though I'd not expect to see such resulting from only a blown primer.

While your .005" over-spec headspace will make your brass expand lengthwise, once it blows forward, that .005" isn't going to ruin your brass or make the life of it appreciably less. Your method of resizing it from then on can. Being .005" over is going to make factory ammo shoot a bit less accurately than if it were spec., though once your brass is fireformed to your chamber and sized properly, this is not the big deal. Cracked necks might also be encountered more often on brass that hasn't been fully fireformed. I have a number of A/R's where I change the bolts occasionally. Sometimes, my bolts create excessive headspace - but, due to careful measuring with proper tools, I KNOW what that headspace is, and I don't use factory ammo in them. Not a problem for me with the dies I use. The idea is to headspace your brass to your chamber by using accurate tools to help properly set up your die (like a Hornady tool for your caliper)- not a reamer print or go-gauges.

I think once you back off your load to a safe level to work up from, your pressure issues will go away. Your .005" excess headspace can be worked with or not - at your discretion. That alone did not result in the high-pressure situation. I have seen my over-pressure rounds have the base expand by as much as .002"+/- and that included a few cases with vertical ruptures. You mentioned .030" on yours. Is that a correct measurement? If so, I'd be inclined to think your primer pockets are likely gone?
.

 

[DShortt]

I still wonder if the powder isn't compromised in some way.

 

[ELR LVR]

I don’t think so.

*Update* today I sent my headspace with the go gauge. After it was set I used 1 piece of scotch tape (.0015- .002) on the back of the gauge and my bolt won’t close so I’m good there. I might have turned the barrel 1/16 of a turn from where it was. Anyway new lapua small rifle brass I started today down another grain so 37.5gr of n160 with a cci 450 primer and smoked and blew out the primer on the first shot at 3058fps. I came down another 1.5gr to 36.0 those 3 rounds stamped the brass hard with an average of 2967. Still over vv max velocity while being 5 grains below their max charge and 1gr below their starting charge. I give up on n160 not worth it to me. I Loaded 3 with 39.0gr of h4350 and had no pressure of any kind 2974 avg fps.

Not 1 thing has added up other than this power is hot as piss in this rifle. No explanation

I can relate, I did not have a good experiene the first time I tried VV-165 myself
Velocity was fine , but accuracy was down the tubes with it compared to standard powders,
I am not on the VV bandwagon myself, when there are so many other powders out there
1 bad experience with a powder is more than enough for myself
Your experience is quite extraordinary to say the least and would imprint a bad memory for years to come.
---------------------------
Glad you switched powders and got it figured out,
4350 has always been a solid accurate performer.
---------------------------
Also I MUST add here, what load works for one rifle may not work for another of the same calibers
Recent experience
(2) different 260 rifles but both chambered the same by me with the same reamer
One Long Barreled faster 8 twist load was safe with 41.0 grns of AA-2700
Second rifle with a shorter slower 9 Twist Starts to show pressure signs with 39.0 Grns
and 41.0 being too hot - again seemingly contradictory to what one would think.
--------------------------
Both rifles worked up with the exact same jug of powder
But both needing to be at aleast 3 grains apart in powder load
Point being - try to take any listed load advice for a particular powder very cautiously
--------------------------
I have interestingly found some very accurate loads when starting much lower than one normally would
such as 5 grains lower then a medium power load and thought "its slow but dang is it accurate"
So that is another added possible benefit to starter lower than most would, you may find a nice low recoiling light load that just shoots extremely well.

 

[DLT]

I can relate, I did not have a good experiene the first time I tried VV-165 myself
Velocity was fine , but accuracy was down the tubes with it compared to standard powders,
I am not on the VV bandwagon myself, when there are so many other powders out there
1 bad experience with a powder is more than enough for myself
Your experience is quite extraordinary to say the least and would imprint a bad memory for years to come.
---------------------------
Glad you switched powders and got it figured out,
4350 has always been a solid accurate performer.

It’s what I always shot in this barrel. That and r-16. I burnt up my 6xc and stuck this barrel back on and had this powder on the shelf sitting. I did what anybody would do and has 1000s of times. I even went with their load data. Something is a miss wish I knew what it was for certain. If it was the primers alone deal or too long of brass, or a combo of the two that would have went away when I changed to new small primer brass. Grrrrrrr

 

[DShortt]

It’s what I always shot in this barrel. That and r-16. I burnt up my 6xc and stuck this barrel back on and had this powder on the shelf sitting. I did what anybody would do and has 1000s of times. I even went with their load data. Something is a miss wish I knew what it was for certain. If it was the primers alone deal or too long of brass, or a combo of the two that would have went away when I changed to new small primer brass. Grrrrrrr

Was the bottle sealed?
I know I am not perfect. Maybe you dumped something in there accidentally?
Mixed powders would definitely explain erratic performance.

 

[ELR LVR]

It’s what I always shot in this barrel. That and r-16. I burnt up my 6xc and stuck this barrel back on and had this powder on the shelf sitting. I did what anybody would do and has 1000s of times. I even went with their load data. Something is a miss wish I knew what it was for certain. If it was the primers alone deal or too long of brass, or a combo of the two that would have went away when I changed to new small primer brass. Grrrrrrr

Ummm , yeah, I got nuthin other than possible extreme humid conditions maybe causing micro condensation in your bore
-------------------------------
IE: Flash evaporation not only slows the bullet down but acts as a ram to try and push the bullet backwards
Probably not it but something to be aware of

 

[William Vogel]

I don’t think so.

*Update* today I sent my headspace with the go gauge. After it was set I used 1 piece of scotch tape (.0015- .002) on the back of the gauge and my bolt won’t close so I’m good there. I might have turned the barrel 1/16 of a turn from where it was. Anyway new lapua small rifle brass I started today down another grain so 37.5gr of n160 with a cci 450 primer and smoked and blew out the primer on the first shot at 3058fps. I came down another 1.5gr to 36.0 those 3 rounds stamped the brass hard with an average of 2967. Still over vv max velocity while being 5 grains below their max charge and 1gr below their starting charge. I give up on n160 not worth it to me. I Loaded 3 with 39.0gr of h4350 and had no pressure of any kind 2974 avg fps.

Not 1 thing has added up other than this power is hot as piss in this rifle. No explanation

Stop using the reloading data for this combination. It’s not aligning with anything for you. Have you used any of this powder from this jug on anything else from your firearms and had successful results aligning at all with published load data? If the answer is no, I’d stop using it. Why not just use the load combination that was successfully tested before. I’m having a similar situation with my 357 magnum pistol right now. Know what I’m doing? Backing way off and saying okay this is what it’s going to be, I probably should have left well enough alone and just put the other powder in it. No one here is with you. We can give you a thousand answers-guesses to what you’re doing wrong. All of which may not be valid and you’re just still looking at blown up brass. Go back to what worked and verify that it still works before using anything that isn’t documented in your gun.

 

[William Vogel]

I don’t think so.

*Update* today I sent my headspace with the go gauge. After it was set I used 1 piece of scotch tape (.0015- .002) on the back of the gauge and my bolt won’t close so I’m good there. I might have turned the barrel 1/16 of a turn from where it was. Anyway new lapua small rifle brass I started today down another grain so 37.5gr of n160 with a cci 450 primer and smoked and blew out the primer on the first shot at 3058fps. I came down another 1.5gr to 36.0 those 3 rounds stamped the brass hard with an average of 2967. Still over vv max velocity while being 5 grains below their max charge and 1gr below their starting charge. I give up on n160 not worth it to me. I Loaded 3 with 39.0gr of h4350 and had no pressure of any kind 2974 avg fps.

Not 1 thing has added up other than this power is hot as piss in this rifle. No explanation

Now I see this.
On my 357 problem both VV and GRT predict MY max load with low pressure and higher velocity but if I go up to somewhere above their minimum and below max, I get damaged brass that I have to knock out of my cylinder. I will say that this pistol requires less than published max on any powder that I put through it. Smith and Wesson 686+ with a 6 inch barrel by the way. It’s a hammer but it’s touchy about the ammunition.

 

[charlie b]

I like VV powders. But, like anywhere else, their load data can be a lot different than what you get. I also use Hodgdon and Sierra data and frequently am ewll below max when I see pressure signs.

FWIW, I have the same model rifle (Savage BVSS) Sierra lists for loads with the .308WWin. I used same components and got vel almost 100fps higher.

In three different guns using N150, N140 and N540 I routinely get higher vel than listed, even with shorter barrels.

One of the biggest differences in most of my load development is seating depth. The reloading manuals typically have fairly short OAL for the cartridges. If you load longer you will see differences. If you load into the lands there will be differences.

Start low, work up.

 

[DLT]

I agree with big5ifty here. Everyone -myself included - likes to take calculated short cuts when we can. This is clearly a case where the powder manufacturers and manual makers have done this "calculating" for us. On the side of extreme safety, we can either assume we know more than them or not, as to where we start on a powder charge. If you start right off with an over-pressure load - you don't know how much to reduce the load. The manuals often also won't tell you how much to reduce a load - as they assume you worked up - and would have seen at what level you had no high pressure - and where you did. When I work up a new load, I do it over a chrono and I only load two rounds at the bottom, then another two, and so on, until I'm getting the velocity range I want to be in with a particular powder - then I do larger groups, with finer incremental changes. So maybe I waste ten rounds and a few more minutes for the barrel to cool. Worth saving what is left of my looks and life. I say this for all beginning reloaders. There truly is inherent danger in what we do, and big mistakes don't happen until they do. If the manuals are followed, it is truly rare for serious problems to occur. Some manuals are much more comprehensive than others and much more explanatory. I personally think the Berger would be one of the top choices for someone starting out. I think if I had been in your situation - after doing this for a "while", I'd have dropped the load to a starting load and worked back up, with the knowledge that part of the problem for the primer escaping the cartridge may have been due to brass that had not fireformed to the longer chamber, creating an "unsupported" cartridge condition by the bolt. The second firing at a lower pressure would likely see all problems disappear.

For bolt damage to occur for your high-pressure rounds, you would likely have had to incur something more than a blown primer to damage the bolt, other than flame cutting from the hot gasses being blown onto your bolt face. I'd still look for a cracked bolt lug or any abnormality in the surfaces of the action - though I'd not expect to see such resulting from only a blown primer.

While your .005" over-spec headspace will make your brass expand lengthwise, once it blows forward, that .005" isn't going to ruin your brass or make the life of it appreciably less. Your method of resizing it from then on can. Being .005" over is going to make factory ammo shoot a bit less accurately than if it were spec., though once your brass is fireformed to your chamber and sized properly, this is not the big deal. Cracked necks might also be encountered more often on brass that hasn't been fully fireformed. I have a number of A/R's where I change the bolts occasionally. Sometimes, my bolts create excessive headspace - but, due to careful measuring with proper tools, I KNOW what that headspace is, and I don't use factory ammo in them. Not a problem for me with the dies I use. The idea is to headspace your brass to your chamber by using accurate tools to help properly set up your die (like a Hornady tool for your caliper)- not a reamer print or go-gauges.

I think once you back off your load to a safe level to work up from, your pressure issues will go away. Your .005" excess headspace can be worked with or not - at your discretion. That alone did not result in the high-pressure situation. I have seen my over-pressure rounds have the base expand by as much as .002"+/- and that included a few cases with vertical ruptures. You mentioned .030" on yours. Is that a correct measurement? If so, I'd be inclined to think your primer pockets are likely gone?
.

Oh yea. No doubt. .030 I have the brass in a bag where I load at or I would take a picture with calipers in place and post it. I think the actual case head measures .469 if I remember right, and the 1 that was the worse was like .495 I think it was. Definitely no primer pocket left and the flash hole is double what it should be. You can see by the pictures earlier in the thread it was more than just a primer getting blown out.

 

[DLT]

Was the bottle sealed?
I know I am not perfect. Maybe you dumped something in there accidentally?
Mixed powders would definitely explain erratic performance.

Yessir. It was sealed. I bought it earlier this year to try in a 22 creedmoor I recently put together. I had no issues with it then. That was the only other chambering I had tried it in. Also the powder all looks consistent in kernel size shape and color to me. The only vv powders I have is n140, n160, and n560

 

[DLT]

Stop using the reloading data for this combination. It’s not aligning with anything for you. Have you used any of this powder from this jug on anything else from your firearms and had successful results aligning at all with published load data? If the answer is no, I’d stop using it. Why not just use the load combination that was successfully tested before. I’m having a similar situation with my 357 magnum pistol right now. Know what I’m doing? Backing way off and saying okay this is what it’s going to be, I probably should have left well enough alone and just put the other powder in it. No one here is with you. We can give you a thousand answers-guesses to what you’re doing wrong. All of which may not be valid and you’re just still looking at blown up brass. Go back to what worked and verify that it still works before using anything that isn’t documented in your gun.

Yes, I used it for testing in a 22 creedmoor With 69gr smk. Did not have any odd problems then. I used vv load data. Noslers was close to the same but with large rifle primers, Nobody else had data I could find. Not hornady and not sierra

 

[DLT]

I like VV powders. But, like anywhere else, their load data can be a lot different than what you get. I also use Hodgdon and Sierra data and frequently am ewll below max when I see pressure signs.

FWIW, I have the same model rifle (Savage BVSS) Sierra lists for loads with the .308WWin. I used same components and got vel almost 100fps higher.

In three different guns using N150, N140 and N540 I routinely get higher vel than listed, even with shorter barrels.

One of the biggest differences in most of my load development is seating depth. The reloading manuals typically have fairly short OAL for the cartridges. If you load longer you will see differences. If you load into the lands there will be differences.

Start low, work up.

I did. I have always started ehh 2 grains lower than max with most anything different I try, unless I’m very familiar with the cartridge and powder. be it different bullet, brass. Never had a problem like this. Noslers data and vv was close to the same best I can remember without going back and looking