Subsonic rifle load data wanted for 303 Brit

[Alex Hamilton]

Thanks, Alex Hamilton. Ummm.... not the answer I was wanting but the truth just the same!

Since starting this thread I have aquired some AS30N (similar to Bullseye, I think). It's bulkier than our AP class powders but faster. I'd say it's not good for very heavy boolits - a bit peaky in pressure if overloaded.

I don't have a load with heavy bullet in 303. but here is one in 7.62x54R Mosin-Nagant. Lyman 313299 weighs 200grs and the Mosin twist is 1 in 9.5 against 1 in 10 in any Enfield. Too close to make a difference.

My only experience with fillers in 303 was with 16grs of Vihtavuori N140 (40% of normal load with 174gr jacketed bullet), topped with 22grs of Semolina, so that there was no air space below the bullet. I fired that the following day, so there was no chance of semolina picking up moisture and clumping. Accuracy was superb. All in in about 1MOA and so quiet that the boys thought I was firing primed cases! But the rifle got very hot after only 10 rounds and the cases were difficult to extract. The problem is that semolina compacts into a solid plug under pressure and firing it in bottle neck cases is not good for your health!!

Regards,

Alex

[303Guy]

Thanks. Exactly what I fear. Of course the mosin is so damn strong (I believe) it won't harm it but a Lee Enfield ...... mmmmm? Wheat bran does not seem to raise the pressure quite as much - very little actually.

[MaxJon]

Thanks. Exactly what I fear. Of course the mosin is so damn strong (I believe) it won't harm it but a Lee Enfield ...... mmmmm? Wheat bran does not seem to raise the pressure quite as much - very little actually.

Yeah i would be very careful with the lee enfield action unless its a No.4 action. Some of us use them without problems. (N0.4s)
BB033

[Jon K]

I haven't checked the speed, but 10 gr of Trailboss works good.....no pressure, good accuracy, mild in the 303(#4 MK1 1943) w/314299 or NOE 316299.

Jon

[303Guy]

All in in about 1MOA and so quiet that the boys thought I was firing primed cases! But the rifle got very hot after only 10 rounds and the cases were difficult to extract.

I've been thinking on the being so quiet and the hot barrel..... I tried a 30gr charge of 4350 under a 204.5gr boolit. First with grits as a filler then with wheat bran (not on the same day). The grits produced a higher pressure as far as primer reading could tell. The recovered boolits looked quite different. I cannot guarentee that the alloy was the same nor that I haven't got my facts mixed up so I'll have to repeat the test but it looks like the grits produced higher pressure but LOWER velocity! Could the COW, like the grits, be resisting the gas pressure, producing friction and consuming all the powder before muzzle exit? Tomorrow I shall load two cases, one with grits, one with wheat bran and boolits of the same weight and alloy.

...be very careful with the lee enfield action unless its a No.4 action.

I use my No4 when I'm unsure of possible pressure but my loads are for a MkI - pre-war so not built under production pressure.

..but 10 gr of Trailboss works good...

I haven't checked to see if I can get Trailboss in my parts. I believe it to be quite expensive.

I'm wanting to try some 4227 with wheat bran filler - I have discovered I have two cans of it!

SOME TIME LATER ...

Well, I got brave enough to try a load of 10gr 4227 with the case filled with wheat bran under a paper patched 140gr boolit. No worries - I' say I could double the powder charge and pressure would still be mild. The powder did seem to burn OK but I didn't have my catch cloth so can't really say for sure. It looks like the boolit was yawing badly on impact - it was a serious reject boolit.

[MaxJon]

I've been thinking on the being so quiet and the hot barrel..... I tried a 30gr charge of 4350 under a 204.5gr boolit. First with grits as a filler then with wheat bran (not on the same day). The grits produced a higher pressure as far as primer reading could tell. The recovered boolits looked quite different. I cannot guarentee that the alloy was the same nor that I haven't got my facts mixed up so I'll have to repeat the test but it looks like the grits produced higher pressure but LOWER velocity! Could the COW, like the grits, be resisting the gas pressure, producing friction and consuming all the powder before muzzle exit? Tomorrow I shall load two cases, one with grits, one with wheat bran and boolits of the same weight and alloy.
I use my No4 when I'm unsure of possible pressure but my loads are for a MkI - pre-war so not built under production pressure.
I haven't checked to see if I can get Trailboss in my parts. I believe it to be quite expensive.

I'm wanting to try some 4227 with wheat bran filler - I have discovered I have two cans of it!

SOME TIME LATER ...

Well, I got brave enough to try a load of 10gr 4227 with the case filled with wheat bran under a paper patched 140gr boolit. No worries - I' say I could double the powder charge and pressure would still be mild. The powder did seem to burn OK but I didn't have my catch cloth so can't really say for sure. It looks like the boolit was yawing badly on impact - it was a serious reject boolit.

Hi 303guy.
Mate,do yourself a favour and save the wheat for your sheep, or send it to me for mine! ha ha. I shoot with about 20 others who shoot subsonic loaded military rifles (mainly 303 Enfields) on a regular basis, and none of us use fillers. If you are so worried about load density save ya bikkies for some trailboss and/or drill out the flash holes of ya brass to 3.5mm dia. with about 7 or 8 grains of your AS30N and you wont have a problem. Assuming you give your undivided attention to your reloading "double charging" should never happen. I use a modified cut off case as a "dipper" that gives me a charge just shy of my desired charge, and trickle the last bit in to the scale pan then immediately sit a projectile in the charged case ready for seating. Time consuming but if accuracy is what you are chasing its the way to go IMO. What ever you do DONT use the drilled out cases for high velocity loads if you value your rifle and your quality of life as you know it! Drilling them gives better and more uniform ignition, when the powder lays below the flash hole when the round is chambered, which will more than likely be the case. Check the link out i posted in a previous reply, (explained better).
Regards,
BB03

[303Guy]

Thanks for the sage advice, bullbarrel033. My problem is I cannot guarrentee I'll never make a mistake! I've got too many different cases and rifles - all 303 Brit - to be able to reliably keep them separate. I have to simply build in large margins for error and multiple safety procedures - and it's paid off more than once. I'd be happy to use a AS30N load that is less than half of max 'though. It's the flash holes that worry me. Will it work OK with a small tuft of Dacron? Or just as is?

There is another reason for looking at the wheat bran route and that is rifling shear on my rust pitted two-groove rifle's bore. Without any WB the rifling cuts through the paper and shears into the groove impression and with WB it does not.

I must say 'though, I like the cleaning effect of the wheat bran!

[MaxJon]

Thanks for the sage advice, bullbarrel033. My problem is I cannot guarrentee I'll never make a mistake! I've got too many different cases and rifles - all 303 Brit - to be able to reliably keep them separate. I have to simply build in large margins for error and multiple safety procedures - and it's paid off more than once. I'd be happy to use a AS30N load that is less than half of max 'though. It's the flash holes that worry me. Will it work OK with a small tuft of Dacron? Or just as is?

There is another reason for looking at the wheat bran route and that is rifling shear on my rust pitted two-groove rifle's bore. Without any WB the rifling cuts through the paper and shears into the groove impression and with WB it does not.

I must say 'though, I like the cleaning effect of the wheat bran!

Hi 303guy, mate the drilled out flash holes work fine with no fillers, check the link i posted for you on post no.34 of this thread, should set your mind at ease! Very informative on subsonic CB loads.
good luck!!!

[303Guy]

Thanks, bullbarrel033. I did go to the link you posted and I did see the article but for some reason it went to a Finnish article on the same topic which I read through then lost the original. Anyway, I saw the enlarged primer but did not take note before the article change (I must have clicked the mouse onto something). Anyway, there are three warnings in the article;

First, highlighted in red.

"The loading of subsonic ammunition should not be undertaken lightly. Done incorrectly or by the incautious or inexperienced, it presents a significant risk of grievous bodily harm to the shooter."

The second,

Don't go below 30% load density!

And the third,

DO NOT use subsonic modified cases for full power ammunition!

And Rule # 7 in red,

7. If load density is less than 40%, use tamping or fillers to keep the powder at the bottom of the case.

I must say I have used lower than 30% load density before with AS30N and AR2205 (and got away with it).

The article also says to lube the bullets. I do that with j-words anyway - prevents copper fouling and it's not a bad idea to keep a layer of lube in a bore in our cool and wet climate. The lube also coats the inside of the suppressore to prevent corrosion.

Anyway, back to sub-sonics. I might just try that suggestion and use my AS30N.

[MaxJon]

Thanks, bullbarrel033. I did go to the link you posted and I did see the article but for some reason it went to a Finnish article on the same topic which I read through then lost the original. Anyway, I saw the enlarged primer but did not take note before the article change (I must have clicked the mouse onto something). Anyway, there are three warnings in the article;

First, highlighted in red.


The second,


And the third,


And Rule # 7 in red,


I must say I have used lower than 30% load density before with AS30N and AR2205 (and got away with it).

The article also says to lube the bullets. I do that with j-words anyway - prevents copper fouling and it's not a bad idea to keep a layer of lube in a bore in our cool and wet climate. The lube also coats the inside of the suppressore to prevent corrosion.

Anyway, back to sub-sonics. I might just try that suggestion and use my AS30N.

Yes i know mate, i read the article form top to bottom, but i and others have loaded hundreds, maybe thousands of rounds varying 7 to 10 grains of FAST BURNING PISTOL POWDERS that would lucky to be 30% density with no problems.
I think if you stick with fast burning pistol/shotgun powders and keep drilled cases seperate from high velocity ones by some sort of identification marks you will be giggling!
Cheers BB03.

[303Guy]

Thanks for all your help bullbarrel033. I've just cast up a few 141gr boolits for the No4 and am about to try out the AS30N. I will be using paper patched boolits but the same rule applies. The benifit of PP is that if the boolit does not make it out the bore it is real easy to push it out! (I'm not allowed to make a noise in my shed so I'll have to start low and work up.) I'll let you know how it goes.

[303Guy]

Well, my small powder measure was set for 5grs AS30N so that's what I used under a 414gr boolit. Cat sneeze! It was a patched boolit and I used only a tuft of cotton wool to position the powder - I'm firing straight down.

Weight retention was 100% fired into sand.

Pressure was so low I thought I would just see what WB filler does. It raises pressure just a little. I then used the same load and WB under a 157gr boolit (no patch) and the end result was the same - cat sneeze and the same expansion of the boolit. Pressure was again just a little higher but still way low. And no leading! So now I have a cat sneeze load to try out on the range.

Oh, by cat sneeze, I mean that's the sound the gun made in the 'test tube'. Boolit performance says supersonic. (The gun is suppressed).

I know some folks will say " what's the WB filler for?" but try it and you'll see.

[MaxJon]

Well, my small powder measure was set for 5grs AS30N so that's what I used under a 414gr boolit. Cat sneeze! It was a patched boolit and I used only a tuft of cotton wool to position the powder - I'm firing straight down.

Weight retention was 100% fired into sand.

Pressure was so low I thought I would just see what WB filler does. It raises pressure just a little. I then used the same load and WB under a 157gr boolit (no patch) and the end result was the same - cat sneeze and the same expansion of the boolit. Pressure was again just a little higher but still way low. And no leading! So now I have a cat sneeze load to try out on the range.

Oh, by cat sneeze, I mean that's the sound the gun made in the 'test tube'. Boolit performance says supersonic. (The gun is suppressed).

I know some folks will say " what's the WB filler for?" but try it and you'll see.

Hi 303guy, turn that cat sneeze into a cat fart and try 7 or 8 grains, should be fine! What distance do you intend to shoot this ammo at? 8 grains should be good for about 150 yards or so.

[303Guy]

What distance do you intend to shoot this ammo at? 8 grains should be good for about 150 yards or so.

As far as possible. Thanks, bullbarrel033, I'll give it a go. I like the sound of 150yds! That would effectively take the range of the boolit out of the equation, leaving it up to me to shoot straight. (I hope this boolit and load will prove accurate).

bullbarrel033, might I ask, do you guys weigh and sort your castings? I've started doing that now that I have an electronic scale (it's not accurate enough for weighing powder charges).

[MaxJon]

As far as possible. Thanks, bullbarrel033, I'll give it a go. I like the sound of 150yds! That would effectively take the range of the boolit out of the equation, leaving it up to me to shoot straight. (I hope this boolit and load will prove accurate).

bullbarrel033, might I ask, do you guys weigh and sort your castings? I've started doing that now that I have an electronic scale (it's not accurate enough for weighing powder charges).

Hi 303guy, I don't weigh my pills, but some others do, and some others buy the Blackhawks CB's. It depends just how serious you are about accuracy, I personally are going to start batching my pills by weight, but have not had the time lately. As far as i have learnt so far about casting consistent pills its all about having the right temp of alloy, keeping your mould hot, and keeping a bit of a rythum for good mould fill out. If you stop casting to do something else you loose rythum which can cause a varience in batches of pills. From my experiences anyway. I also think cast iron moulds maintain heat better than alloy ones, the alloy ones tend to cool a lot faster, a bit like a heatsink effect if you know what i mean?
Cheers BB03

[303Guy]

Well, I loaded up some cat sneeze loads and took out for a trial. They don't work worth a damn! Just not not enough pressure por a patched boolit. I will pull all the remaining boolits and try plain lubed.

[MaxJon]

Well, I loaded up some cat sneeze loads and took out for a trial. They don't work worth a damn! Just not not enough pressure por a patched boolit. I will pull all the remaining boolits and try plain lubed.

Yeah 303guy,
I know nothing about paper patched pills, or the process/benefits etc..... Not sure i want to. Did you try the drilled flash hole case?? Sure improved accuracy in my Mauser!!
Hang in there!!
BB03

[303Guy]

No, I didn't try the flashole trick yet. I should have known better than to load up so many of an untested load. I'll make up a mold for plain cast next and substitute them for the patched ones. I just couldn't find my bullet puller today! It's gotta be somewhere.

[stocker]

303guy: The only subsonic loads I've played with involved lead round ball in 348 Win and 35 Whelen. The powder used was 5744 which didn't appear to be position sensitive as far as I could determine. I got excellent 25 yard accuracy using 6 grains (35Wh.) and 8 grains (348 Win). Double or even triple charging would not be a problem with 5744 using the lighter round balls but accuracy falls apart fast when the speed goes up very much.

5744 is a safe powder to reduce a lot so you may find what you want using it with a bit of experimenting. With your heavier boolits you would probably need more powder than I used but just how much is the question. I think I would start about 10 or 12 grains and go up from there until you're happy.

[303Guy]

Thanks stocker. Not knowing the powder I did some research on it. It sounds like just the ticket! (Not sure if I can get it in my parts - I'll check).