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As I already mentioned, Remington make a 174 grain, flat base FMJ projectile in their line of Remington-UMC target ammo. I'd guess it's loaded to Mk.7z specification but most don't want to pay the price per box. Dealer cost on the ammo is $21 and change a box. It simply doesn't compete price wise with the PPU and S&B that's produced overseas to Mk.8z spec.. For many folks, reloading is the only option. Some may remember when I tried in 2012 to get the engineers at Sierra to think about producing a Mk.7 projectile or at least one with the same flat base performance and failed miserably. I supplied pulled nos projectiles and dimensional drawing etc but to no avail. Of course, if I had dropped thousands of dollars up front, they would have done a run but that ain't gonna happen. I think all of the big bullet manufacturers are missing the boat on this one.
Remington should market the 174 FB FMJ .311 projectiles in bulk like they do 7.62 and 5.56 but they don't do it. The problem would be solved.
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Thank You to Brian Dick For This Useful Post:
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01-08-2017 11:47 AM
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Yep Pete, it's a good word and applies equally well in this instance.
I remember doing a test on the different types of 303 projectiles a fair few years ago, results were posted on one of the forums, but don't remember which one.
Yes, some of the comments about boatails is correct, but only in respect of Milsurp Wartime style projectiles.
Modern Boattails are a totally different kettle of fish, softer jackets, larger bearing surface and are capable of bumping up to seal most of the battered and beaten barrels around.
Although I lost a lot of pics in the big crash, somewhere on one of my many computers, there should be the odd pic or two, like this one........
Attachment 79513
This one shows different projectile shapes in 303 pills, the Mk.VII flat base, Mk.VIIIZ boattail, and both Hornady and Sierra modern boattails.
Now note the profile of each pill, straight sided, full boat shape, straight with short boattail.
As you can see, the Mk.8 is fully rounded, only the smallest surface is in contact with the bore, limited chance of base bumpup, creating blowby in barrels with throat erosion or excessively worn lands and is subject to upset in the barrel, leading to excessive yaw on exit.
Which increases the reports of keyholeing that we see..........doesn't matter a toss in a MG.
Now look at the modern pills, long bearing surface(creates stability) short tail,and a soft jacket to boot.
Allowing these pills to partially bump and create a fair seal in pretty bad barrels.
Having done extensive firing tests on all these types(even shot a hole in the pool liner) my conclusions were that the modern projectile would bump up quite adaquately, givind good to acceptable accuracy in most barrels.
The barrel testing phase of this trial was conducted using a Chronograph.
All bad performance/keyhole effects were attributed to a loss of velocity, the muzzle velocity in a few bad barrels dropped below an exceptable level I.E. 1850FPS, whereas rounds that did not upset had a muzzle velocity above 2200FPS.
By diligent handloading(still using BT's) the velocity was increased to get the figure to an acceptable level(2000fps) where these barrels began to stabilise and give an acceptable level of accuracy.
Now some of the barrels trialled, were very bad, I expected jacket stripping and shearing, but to my surprise, other than one totally wasted barrel, the soft pills held together and bumped up to an exceptable level.
I could go on about this for hours, but I'm well past the days when I get a sore forehead from bashing my head against a brick wall.....so bollocks to all the disbelievers, you could learn something if you were willing to experiment, might even surprise yourself.
Time to put the milsurps ammo away, stop eroding your love toys away and give them a new lease on life.
Reloading is much easier on them anyway..........you can even molycoat to reduce the friction............and could be pleasantly surprised at the increase in accuracy.
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Bindii, Petes just a dyed in the wool bloody pom, you'd think he would have learned something working out here with us ozzies (woops, no emogee for a flak jacket)
Found a pic that I commented on years ago, boattail fired in a 2 groove poor cousin.
Attachment 79514
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Originally Posted by
muffett.2008
Bindii, Petes just a dyed in the wool bloody pom, you'd think he would have learned something working out here with us ozzies
(woops, no emogee for a flak jacket)
Found a pic that I commented on years ago, boattail fired in a 2 groove poor cousin.
Attachment 79514
He thinks he is safe back in Old Blighty.
Muff my trials started with why didn't 125gn Taipans group like the Mk7s followed by 150gn etc all the way out to the 212gn Mk6. The Poms ( say that quietly somebody might hear) worked out what worked best. then when they needed more velocity the 174gn with a light front, heavy rear appeared, all opened base because cordite was very erosive there fore requiring upset from a projectile. The flat base never gave me this except the heavy Taipans. So conclusions were minimum weight to length (only just) was 150gn FB, open base were the best unless the BT took away to much bearing surface. and the dreaded keyhole appeared. The light weight front certainly plays a major part in the length to weight ratio.
2 groove Savage was also used with a No1 Lithgow H barrel both range rifles. Nobels and IMR powder. Ran a shorter test with a BSA No5 some years later. Same conclusions.
The modern powders (ADI ) certainly have changed the state of play with higher velocities at lower pressure as I found with the No5 though the order did not change.
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Hey Muffer, Bindi and Cinders. Being in Oz all that time and working hard and in tough situations taught me never to take things to heart. Stood me in good stead later. But back to my idea of spreading the boat tails. It'd need a lever pressing a ball bearing down into the centre and that'd do the trick. I might knock something up this afternoon.......
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Hey Muffer, Bindi and Cinders. Being in Oz all that time and working hard and in tough situations taught me never to take things to heart. Stood me in good stead later. But back to my idea of spreading the boat tails. It'd need a lever pressing a ball bearing down into the centre and that'd do the trick. I might knock something up this afternoon.......
Peter I have a Corbin bullet making press and dies. By making another core stuffing die, modifying a shaping die I now have a means of turning OBBT into OB non BT. I don't think this setup would work with closed base boat tails. The jacket would have to be moved to much and rupture. The core would probably move forward as well
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Like I said Bindi. I'm not a reloader just an engineer with a head full of ideas. But I'm not sure that the copper would split over the small amount that it would need to spread. After all, it's already been spread once and then rolled back and over. to make the bullets you have Not sure how the lead core could move forwards unless there was already an air gap ahead of it and while it'd spread out of course, you can't compress it. I know......., I know......., someone will come on within an hour and tell me that you can compress it...........
Pete the Pom
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With FMJ the base is open, military style. Hunting or other civvie style bullets BT or FB the opening is in the front reverse manufacture.
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Thank You to Bindi2 For This Useful Post:
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I think the reasoning behind the solid base on commercial projectiles is to reduce the risk of jacket shedding.
The yanks and their silly Saami requirements are all aimed at reducing litigation.
Still, these jackets shed on the face of a coreflute target half the time, I'm often cutting myself on the jackets left behind...........maybe I should do less marking and more shooting.......take more care of my digits.
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