Powder speed for browning BAR 30-06

[Rusticlease Shackiforous]

So I'm about to start working up a load for my BAR. The Honady manual lists 11 powders ranging from Alliant RL-15 to SUPERFORMANCE. These powders are for the 190gr. Interlock BTSP that I have my eye on. I'm wondering what speed powder would be best for the BAR's gas system. Fast? medium? Slow? Any advice on where I should start?

 

[Decoy80]

I use CCI Large Rifle primers along with IMR 4350 and about a medium load. Decent accuracy and easy on my action. Mine just says Belgium patent pending on it and is the nicest thing in my little collection so I don't try to do wonders as far as loads go. BTW I wonder what year the patent was still just pending. I have a 300 magnum BAR 2 that says made in Belgium and assembled in Portugal and I think it may have been made just before the work went to Japan. I load light for it also. If I want to get serious I do that with my bolt action guns.

 

[Slamfire]

I don't have a BAR, I have Garands. As a general rule, faster burning powders are better than slower burning in gas guns.This all has to do with the residual breech pressure at unlock. These guns were designed to unlock while there still is some pressure in the barrel, this pressure helps pop the case out of the chamber. The pressure is on the order of 650 psia. If you are using a powder that gives too high of a breech pressure, you will rip rims, and you will over accelerate the mechanism, leading to battering and malfunctions.

For 30-06 Garands, for decades the advice has been not to use powders faster than IMR 3031 and not slower than IMR 4064. IMR 4895 was the service rifle powder, it was used as the 30-06 propellant in WW2, Korea, etc. It was the powder used in the National Match ammunition. For 30-06 semi auto, any of the 4895 powders, that is H4895, AA2495, or IMR 4895, should be the first choice for experimentation.

I would not use 190 grain bullets, I would stay with bullets from 150 grains to 175 grains, though shooting lighter bullets than 150 grains is just fine. Heavier bullets cause function issues, mainly gas port pressure issue.

I doubt Browning will provide any advice about reloading, but you could call them and ask if the mechanism will handle 190 gr factory ammunition.

 

[Bart B.]

These guns were designed to unlock while there still is some pressure in the barrel, this pressure helps pop the case out of the chamber. The pressure is on the order of 650 psia.

Never heard of that. The 10,000 psi at the gas port isn't enough by itself?

Any military document around to verify it?

Is that the pressure in the barrel when the bolt unlocks and the bullet is several feet down range? The bolt goes back starting at 25 fps; the speed the op rod is moving it.

It (4895) was the powder used in the National Match ammunition.

Only because it metered more uniform than 4064 that was better for accuracy with weighed charges.

 

[Decoy80]

Slam fire, Im not trying to steal the OPs thread or lead anyone astray. I have a little IMR 4895 to load a few to try. I havent been having any problems as of yet with IMR 4350. It is slower burning but Ive loaded light to medium so as not to hurt my actions in both the 06 and 300 mag. I will try the faster powder since I have a little in my 06. I dont think I should try anything different in my 300 as It has served well for 20 years now. Thanks for the comment It might be a better combo.

 

[Slamfire]

Never heard of that. The 10,000 psi at the gas port isn't enough by itself?

Any military document around to verify it?

Is that the pressure in the barrel when the bolt unlocks and the bullet is several feet down range? The bolt goes back starting at 25 fps; the speed the op rod is moving it.

These are all from Chinn's Machine Gun Book Vol IV. A book everyone ought to read to understand the principles of semi automatic and full automatic mechanisms. Chinn’s series can be downloaded for free at Hyper books: http://www.ibiblio.org/hyperwar/USN/ref/MG/

The first section everyone ought to read is the simple blowback, as the concepts of residual breech pressure, case lubrication, timing, are first presented there.











This is also important, cartridge movement out of the chamber during the residual blowback period.


The Oerlikon used the rebated rim shown below and the mechanism was an advanced primer ignition. To make the Oerlikon function the cases had to be greased. All Oerlikon's used by the Americans, Germans, and Japanese during WW2 used greased cases. Of course pre greasing cases was messy and after WW2 the US installed oilers. I know Oerlikons with oilers were used in Vietnam, a shooting buddy stole one from the USAF and installed it on his river barge! Anyway the long chamber of the Oerlikon allowed much more case movement as the residual pressure dropped, as shown in this picture.



Chinn's book are free to download, but there are some excellent hardcopy books that explain the operating principles of small arms. One I recommend is Small Arms by D. F. Allsop. https://www.amazon.com/Small-Arms-M...=1486487191&sr=1-2&keywords=small+arms+allsop This book, in section 5.0 Introduction to Operating Mechanisms, pg 53, shows a typical pressure and time curve and when unlock occurs.

Only because it metered more uniform than 4064 that was better for accuracy with weighed charges.

Nothing wrong with IMR 4064 in the 30-06, and nothing wrong with IMR 4895 in the 30-06.

 

[Slamfire]

Slam fire, Im not trying to steal the OPs thread or lead anyone astray. I have a little IMR 4895 to load a few to try. I havent been having any problems as of yet with IMR 4350. It is slower burning but Ive loaded light to medium so as not to hurt my actions in both the 06 and 300 mag. I will try the faster powder since I have a little in my 06. I dont think I should try anything different in my 300 as It has served well for 20 years now. Thanks for the comment It might be a better combo.

I am very familiar with the 30-06 in gas guns, don't have a 300 Magnum at all. If what you are doing works, by all means, keep it up. I am just trying to provide general advice on the things, and I know what has worked for me.

 

[Bart B.]

Good info on blowback, Slamfire. Any info in that article specifically relative to chamber pressure for M1 bolts completely unlocked .004 seconds after firing and the bullet's 90 inches past the muzzle?

I ask because my stuff cannot download that link's files for Vol iV.

 

[ReloaderFred]

I've been loading for my Belgium made Browning BAR since 1969 in .30-06 with IMR 4320 and a 165 gr. Hornady BTSP bullet. It's proven to be very accurate, and I've taken everything from ground squirrels to elk with it. That powder and bullet combination has been tried and true for me for over 48 years with that particular rifle, and it still shoots straight and true to this day.

Hope this helps.

Fred

 

[ArchAngelCD]

So I'm about to start working up a load for my BAR. The Honady manual lists 11 powders ranging from Alliant RL-15 to SUPERFORMANCE. These powders are for the 190gr. Interlock BTSP that I have my eye on. I'm wondering what speed powder would be best for the BAR's gas system. Fast? medium? Slow? Any advice on where I should start?

While the Hornady manual lists 11 powders for the 30-06 not all are suitable for your BAR. I suggest you use the data in your manual for the M1 Garand a few pages past the page you're looking at now. You will notice they do not list bullets weighing over 178gr or lighter than 150gr and they do list plenty of powders they do not list the slower powders like Superform.

I use mostly H4895 for 30-06 ammo meant for a semi-auto while I much prefer H4350 for the 30-06 in a bolt action rifle. If my M1 was in .308 Win IMR4064 would be my choice.

 

[Slamfire]

Good info on blowback, Slamfire. Any info in that article specifically relative to chamber pressure for M1 bolts completely unlocked .004 seconds after firing and the bullet's 90 inches past the muzzle?

I ask because my stuff cannot download that link's files for Vol iV.

That is unfortunate that you cannot download Chinn's series. All I have to do is right click on the underlined Vol IV link and "save as", and the document is saved to my computer. The information you are asking for would only be in an Army Technical report, assuming they documented the information and the report still exists.

 

[Rusticlease Shackiforous]

I have read the service rifle section of the Hornady manual. I did notice they were using lighter bullets. Is this because of the pressure ratings of the older guns? My bar is a 68.

 

[Rusticlease Shackiforous]

BTW I wonder what year the patent was still just pending. I have a 300 magnum BAR 2 that says made in Belgium and assembled in Portugal and I think it may have been made just before the work went to Japan.

According to Browning, mine is a 68 grade II. I didn't notice "patent pending" on mine while I was trying to date it. I'll check again and see if it is there.

 

[Sunray]

30-06 Garands run at 50,000 psi. Max loads for 150's run between 46,000 and 59,300 PSI(there are some CUP pressure numbers too.) So do 190 grain loads.
There's no mention of "gas port pressure" in any U.S. military manual. No mention of it in any of General Hatcher's books. No mention of it anywhere but on assorted internet forums.
Anyway, if there were any ammunition issues with a commercial hunting rifle like your BAR, Browning, et al would have put it in their manual. I'd use what are considered normal powders for .30-06 and load for accuracy. Wouldn't use a 190 either, but only because the .30-06 doesn't need that heavy a bullet. Any 165 grain bullet will kill any game in North America you care to hunt.

 

[Rusticlease Shackiforous]

I want to play with it and see what it will do. That's why I was looking at some bullets with higher BC's. I really don't hunt much. I'm one of those guys that enjoys books, tools and the process. I don't want to be too hard on the old girl, but I'd like to see what she can do!

 

[dgod]

Try the ELD-X bullets, I have had superb luck with them, I scale each load, then go to the range with usually 10 rounds in a set, I chrony each test set, document each piece of data, then look at the data, make adjustments if necessary, and start over. The ELD-X gave me an Extreme Spread of 49 fps, and Standard Deviation of 12 fps, 300 Win Mag, 5 rounds within 0.65". If you start slow, and work up slowly you too can get that performance. I think the lightest Hornady ELD-X is 178 Grains, I agree that you probably don't want to get into the Heavier (200, 212, 220 grain) bullets. I also had good results with a 150 grain Spitzer too.

 

[Bart B.]

30-06 Garands run at 50,000 psi.)

No. Those 50,000 psi numbers are mislabeled CUP pressures that the military Arsenal people used but were not smart enough to stop confusing everyone. That approximates 60,000 psi using pressure transducers.

Read about Garand port pressures in

http://www.forgottenweapons.com/wp-content/uploads/Garand/Navy Garand 762 Conversion Report.PDF

 

[Rusticlease Shackiforous]

I agree that you probably don't want to get into the Heavier (200, 212, 220 grain) bullets.

Yup. I just dug up a target from when I sighted it in years ago (that component/ammo scare really robbed years off of my shooting life). The best groups I had were with 150gr. sst factory ammo. Man... hahaha... I'm just glad I can get back to it. I was going to start reloading years ago. All the components dried up right before I ordered my press.

 

[Rusticlease Shackiforous]

It's actually kimd of funny... when I say "dug up", it was actually more like randomly looked up and remembered that the old target was used to close up an attic access hole in the shop...

 

[Decoy80]

According to Browning, mine is a 68 grade II. I didn't notice "patent pending" on mine while I was trying to date it. I'll check again and see if it is there.

I probably souldnt hunt with mine as its in the best condition of my humble hoard. My wife and daughter might get the most for it due to its age and lack of rough treatment. It is just a tool but unlike the others recieves special treatment. Some of mine are pretty beaten up from use and not pretty. I have spared it from hunts in a lot of thick brush,briars and brambles. It also gets to ride cased and the others ride where it is most convient to my needs not theirs, wear and tear to their looks, they arent allowed such comfortable conditions.

 

[judgedelta]

I like the Sierra Gameking 165 grain bullets. I load the spire points at 3.330 and the hollow points at 3.185 RL-15 at 46.4; IMR 4895 at 44.7 and IMR 4064 at 47.5. My BAR will shoot into an inch with these loads (if I do my part...)

 

[entropy]

I used IMR 3031 and 4064 in my 742, but with 150 and 165 gr. bullets only. Accuracy and function were exceptional for a "Jam-o-matic", as so many call Remington autos.