.040 and pressure

[rangeball]

Something else I've been wondering about is the affect the larger flame channel and flash hole will have on pressure of known loads. TG has performed a wealth of testing to keep us safe and knowledgeable, but unless I missed it almost all of this was with the standard .030 vent?

Looking at his trace data shows 78gr of H4198 with a 275gr BE yields around 43kpsi (from memory, looked a few days ago). With a .040 bushing and larger flame channel providing more complete ignition and likely quicker obturation it makes sense to expect the PSI to increase, right? But how much?

[Dave W]

Look in the I section Mike. Several .041 bushing traces are there, not sure about the enlarged flame channel though.

[rangeball]

Will do. I quit scrolling when I hit the first 78gr 4198 load

[bestill]

I been watching
040 results and wondering if having to increase flame channel volume.

I have a .031 vent and a flame channel thats .140 i.d and .780 long which is .012 cubic inches. When channel carbons up to appx .100 id primer bulge is significant which is .006 cubic inches. Usually appx 25 shots this happens.
So back to the.040. If i use a .040 bushing with existing clean plug.012 cubic inches volume primer bulge is significant.
My simple mind feels yes you get more fire to ignite powder but i feel you get more reverse flow also to primer before bullet exits and pressure drop.
Thanks hope makes since. Seems a balancing act . Id like to see flame channel volumes listed with bushing size and results yall are getting.

[Deleted]

Aug 29, 2014 16:19:54 GMT -5 bestill said:

I been watching
040 results and wondering if having to increase flame channel volume.

I have a .031 vent and a flame channel thats .140 i.d and .780 long which is .012 cubic inches. When channel carbons up to appx .100 id primer bulge is significant which is .006 cubic inches. Usually appx 25 shots this happens.
So back to the.040. If i use a .040 bushing with existing clean plug.012 cubic inches volume primer bulge is significant.
My simple mind feels yes you get more fire to ignite powder but i feel you get more reverse flow also to primer before bullet exits and pressure drop.
Thanks hope makes since. Seems a balancing act . Id like to see flame channel volumes listed with bushing size and results yall are getting.

Earnhardt is reporting no carbon build up with the .040 bushing self cleaning maybe....He opened up the flame channel and has been good to go so far....Check with him on specifics....

[Deleted]

When I first started with the .416's with .020" bushings and a standard primer flame channel, the primer flame channel would "crud up" much faster with the .020" bushing in the .416, than with a .030" bushing in the .45's.
The more crud that was in the primer flame channel the smaller that air volume would be, and the faster and more severe the primer bulging would be.

Apparently in the past, some guys would want or leave primer channel crudded up, since the vent liners would last longer because it allowed less gases back through the vent hole to erode the vent liner.

I would start out with a clean standard sized flame channel with a T-Rex 416 load and a .020" bushing.
There wouldn't be any primer bulging at all, but once the primer crud started to build up the worse the bulging became.
I'd go clean the crud out of the flame channel, and shoot the same load, and there wasn't any primer bulging. So the crud in the primer flame channel was indeed causing the primer bulging.
So that's when I first started thinking about bigger primer flame channels and their effects on primer bulging.
bestill was the first to show us his results of the bigger primer flame channels.

With the bigger flame channels and .040" bushing, there is absolutely no primer crud build up in the plug. Only a "dust" or residue coating.
So, I THINK, all of the primer gases and metal flyings are being pushed through the bigger primer flame channel and .040" bushing into the powder charge.

With the big IMR 4831 loads that I'm using to push the 325 MH at 3150 fps in my .451, the smaller the primer flame channel, the more primer bulging there is.
So, I THINK, even though there is a bigger volume of air in that flame channel the pressures are lower.

So yes bestill you are right in saying there will be a cataloging of sorts when it comes to the various sized primer flame channels we use with various loads.

Normally I'm shooting the 300-325 MH's from 2950 to 3150 fps. So automatically, I'm drilling the primer flame channels out to 14/64" and 15/64".

That's why I'd like Richard to start with a 10/64" (5/32" I know) flame channel with the loads he uses.
Because the loads he shoots every week are the same loads that the vast majority of us use when we are hunting.

I'm going to shoot some "standard loads" of 70 grains of H4198 with a 300 MH to see if the 15/64" primer flame channel is beneficial or detrimental to that type of load in the .45's.

I don't know if it's a science yet, but more of an art, when it comes to determining the size of the primer flame channel relative to the load.

Catalogging of loads over time will pinpoint various sizes the primer flame channels need to be.

But for right now, I'm hoggin' my primer flame channel out to 15/64" and pouring the coals to it. And the primers don't bulge and the super slow powders ignite without boosters or super tight bullets.

[Deleted]

Aug 29, 2014 20:27:48 GMT -5 Earnhardt said:

When I first started with the .416's with .020" bushings and a standard primer flame channel, the primer flame channel would "crud up" much faster with the .020" bushing in the .416, than with a .030" bushing in the .45's.
The more crud that was in the primer flame channel the smaller that air volume would be, and the faster and more severe the primer bulging would be.

Apparently in the past, some guys would want or leave primer channel crudded up, since the vent liners would last longer because it allowed less gases back through the vent hole to erode the vent liner.

I would start out with a clean standard sized flame channel with a T-Rex 416 load and a .020" bushing.
There wouldn't be any primer bulging at all, but once the primer crud started to build up the worse the bulging became.
I'd go clean the crud out of the flame channel, and shoot the same load, and there wasn't any primer bulging. So the crud in the primer flame channel was indeed causing the primer bulging.
So that's when I first started thinking about bigger primer flame channels and their effects on primer bulging.
bestill was the first to show us his results of the bigger primer flame channels.

With the bigger flame channels and .040" bushing, there is absolutely no primer crud build up in the plug. Only a "dust" or residue coating.
So, I THINK, all of the primer gases and metal flyings are being pushed through the bigger primer flame channel and .040" bushing into the powder charge.

With the big IMR 4831 loads that I'm using to push the 325 MH at 3150 fps in my .451, the smaller the primer flame channel, the more primer bulging there is.
So, I THINK, even though there is a bigger volume of air in that flame channel the pressures are lower.

So yes bestill you are right in saying there will be a cataloging of sorts when it comes to the various sized primer flame channels we use with various loads.

Normally I'm shooting the 300-325 MH's from 2950 to 3150 fps. So automatically, I'm drilling the primer flame channels out to 14/64" and 15/64".

That's why I'd like Richard to start with a 10/64" (5/32" I know) flame channel with the loads he uses.
Because the loads he shoots every week are the same loads that the vast majority of us use when we are hunting.

I'm going to shoot some "standard loads" of 70 grains of H4198 with a 300 MH to see if the 15/64" primer flame channel is beneficial or detrimental to that type of load in the .45's.

I don't know if it's a science yet, but more of an art, when it comes to determining the size of the primer flame channel relative to the load.

Catalogging of loads over time will pinpoint various sizes the primer flame channels need to be.

But for right now, I'm hoggin' my primer flame channel out to 15/64" and pouring the coals to it. And the primers don't bulge and the super slow powders ignite without boosters or super tight bullets.

Thanks again for all of your time and money spent doing all of this testing and sharing your findings with us, you're doing the leg work for many of us and it is beneficial to many of us, so thanks again. You have definitely surged ahead and opened many new doors.
Great work!

[Richard]

Got you on the flame channel size Earnhardt!
Richard

[rangeball]

Earnhardt, doesn't that point to the largest flame channel possible with a .040 flash hole offering the best ignition potential in a .458?

[jims]

I will watch with interest how this proceeds. I would like to get the tungsten BP, just waiting to see what is the best for the .45s.
Perhaps a different size for .40, .416., .45 and .50.
I and others appreciate the time,effort and money expended in the continuing quest for better ML.

[Deleted]

Aug 29, 2014 20:57:33 GMT -5 rangeball said:

Earnhardt, doesn't that point to the largest flame channel possible with a .040 flash hole offering the best ignition potential in a .458?

You're right. It does point to that.

But when bestill whipped out the "E=mc2", when it comes to primer flame channel volume and a particular balance when it comes to loads and primer flame channel size, I'll take the conservative route at first.
And go his route with a smaller primer flame channel with the "standard" loads.

Who knows, when Richard works his way up to the 14/64" (7/32") flame channel, maybe we'll find out the 14/64" primer flame channel will work with all loads that are using a .040" bushing.

At this point, I truly don't know because I'm not shooting the same loads that Richard is.

[Deleted]

Aug 29, 2014 21:28:09 GMT -5 jims said:

I will watch with interest how this proceeds. I would like to get the tungsten BP, just waiting to see what is the best for the .45s.
Perhaps a different size for .40, .416., .45 and .50.
I and others appreciate the time,effort and money expended in the continuing quest for better ML.

Thanks for the comment.

Right now I've only made my way up to a .035" bushing with my new .416. And that's with a 14/64" flame channel.

With a 350 MH at ~3050 fps with H1000, there isn't any primer bulging, with no crud build up. And the ignition is flawless with ES's from 3-14 so far.

And I've found H1000 to be a very hard powder to ignite with smaller diameter bushings without a booster, and with the LRMs.

Before I started using a plug with a drilled out flame channel the 209's would be toast with a larger bushing.

Some of the guys shooting the .40's and myers129, with an upcoming .375, can share info with us when it comes to a bigger primer flame channel with large holed bushings.

Time will tell I guess.

[Deleted]

I know, I know, I have maybe two weeks left and we can fire her off Josh! Gotta get busy been slacking far too long on this project.

[ET]

Earnhardt

You’ve helped bring ML to another level with your time and effort so nicely done.
Igniting slower powders without a booster is an accomplishment I enjoy seeing as I prefer using a single powder over duplex.
Currently your goal is to eliminate 209-primer bulging so as not to hinder your load development.
Currently we have no high pressure indicator where a designated max load is being approached.
If it could be established that at a specific pressure level with a specific primer and specific BP configuration where 209 primer bulging is starting to appear this may be used as an indicator for the shooter forewarning him of approaching too high a load pressure. To some this may be a desirable option to have.

Just a thought for observation consideration while adjusting your BP configuration.

Ed

[hemicuda]

Earnhardt, how does the flash hole hold up with those heavy loads? Are you using titanium bushing? Are you getting a complete clean burn without booster powder? We are still shooting in warm weather so things are working well as opposed to cold deer temps.

[Deleted]

Aug 30, 2014 8:25:39 GMT -5 hemicuda said:

Earnhardt, how does the flash hole hold up with those heavy loads? Are you using titanium bushing? Are you getting a complete clean burn without booster powder? We are still shooting in warm weather so things are working well as opposed to cold deer temps.

The bushing hole looks great. Even with heavy loads. Retumbo in the 416 causes the most erosion if all the powders. Even with loads around 42 kpsi.
Its a pure tungsten bushing.
Yes its a complete clean burn without a booster. I haven't shot it in cold weather, once it gets from 0 to -30 I'll post results on ignition.

[Richard]

Well, I got lucky at the 600 yard match today....................No, I did not shoot all that well(OK) but I did score an 8 lb. jug of H-4198 from a friend who owns a Pawn Shop! ($215.00) I was down to my last 1/2 lb.
Richard

[cuda]

The last gun show I went to I almost bought a 8ld jug of IMR4198 for $150 but I still have 5lbs on hand now. $215 sounds a little high on price to me but from here to where you are the price could be really good.

[Deleted]

150 for 8lbs would be exceptional... Was 2/3 of it missing