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> Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)
Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)
@ 09:34 pm (GMT) |
Alvaro PiquerasHello folks;I have a Winchester Model 70 (post ‘64) chambered in 264 Win Mag. The rifle is in good condition, and it´s probably my best choice for LR hunting. I can use a 7mm Mauser, a 243 Win or a 22-250 instead os the 264WM, but I think that this is the best choice. But I have a complaint… the barrel is the sporter contour and it´s only 24” long. The sporter contour doesn´t seem to be a big problem… Just work up loads till get a sweet spot, letting the barrel cool between shoots. But I know that the 264 is critical with the barrel length. Put in a new barrel could be the easiest option, but in Spain this is a very expensive option, so it´s discarded. So I think that the option will be choose a lightly slow burning powder and a correct bullet selection… Here in spain, the reloaders have to fight with very restricting laws, and the only powder wich is legalized is Vectan (france powder, by Nobel Sport). I have Tubal 7000 (burn rate similar to IMR4831, Winchester 785, reloader 19) and Tubal 8000 (burn rate similar to Norma 165, IMR 7828SSC, Accurate MagPro, reloader 22) Now I have 130 gr Barnes TSX (not tipped) and 140 gr hornady SST. Last tests give me 2670 fps with the barnes 130 gr and a light, but accurate, load of tubal 7000 (52 gr, having tested till 56 with no over-pressure signs), and just 2600 fps with the 140 SST testing a faster burning powder (tubal 5000). Any help on that? What speed could I spect from this barrel? What is the best bullet selection for this rifle (shoots from 150 meters out to 500… maybe further when I get ready) Is better to choose heavier bullets to get better BC, to maintain the muzzle velocity? I think that my way could be the 140 SST or the 140 A-MAX. Thanks a lot! |
Replies
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@ 10:37 am (GMT) |
Nathan FosterRe: Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)Hi Alvaro, you want to try and get the rifle shooting about 3030fps with the 140gr SST or A-Max. It may go faster, but somewhere around 3030fps should be about right.Try to keep working up loads. Allow about 40fps per grain. Take it right up till you find near maximum (about 3100fps will be near max with the 24" barrel). Use the SST inside 250-300 metres. On Red deer and Boar, you can use the SST out to fairly long ranges but it is not as good as the A-Max. Use the A-Max from 250 metres out to about 700 metres. You can use the A-Max at close ranges on light game like Roe/Rei. But on red deer or wild boar, the 140 grain A-Max can suffer shallow penetration at close ranges where velocity is very high. You can if you wish, use just the one A-Max load on everything. This just means that at close ranges, you go for neck shots or just behind the shoulder rather than the centre of the shoulder. I hope that all makes sense. The rifle may need to be bedded. Sometimes in an unbedded rifle, you can get the speeds up but once you get the bullet going fast, accuracy is poor. So you will need to keep this in mind. Cheers, Nathan. |
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@ 06:53 pm (GMT) |
Alvaro PiquerasRe: Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)Hi Nathan!Thanks a lot for your help. I have bedded the rifle with acraglass gel. This kit it's about to end, so i will order a bedding kit to you. After the first bedding job, it seems to be nice, but when i tight the action screws the stock bends and contact with the barrel. I have bedded a few rifles (not a lot of them) but i didn't expect that... So i try to fix it: remove a few of bedding compound and re-bedded it, trying to make some kind of pillars with the epoxy. The epoxy goes from the bottom of the stock to the action. I remove the action today and it seem to be good. Let me know if you like to see some pics. I have get another powder, it's a double base powder somewhere between tubal 7000 and tubal 8000. This seem to be the best choice in our restricted offer. I'm nervious to start the working up loads, and to use the sightron big sky scope! I will keep the forum posted. Hope this help![b] |
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@ 03:26 pm (GMT) |
Nathan FosterRe: Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)Hi Alvaro, yes, please send pictures to my email account, I will check the job over for you as best as I can.To test whether the bedding job you did has placed any stress on the action, hold the rifle at the 1 oclock position, release the floor plate/mag spring, then undo the middle screw so that it is loose. Next, loosen the front action screw a turn. As you do this, look to see if the barrel tries to climb up and away from the stock. Tighten and loosen this front action screw a few times to recheck this. If the metal work tries to climb out of the stock, it means that the action is under stress and that the rifle needs re-bedding. When you finally assemble the rifle, make sure that the middle screw is done up firmly but not tight. If the middle screw is tight, the action will be placed under great stress as will the stock. This will effect accuracy. If you are worried that the middle screw is too loose and that the tension might change and effect groups, apply Loctite to the middle screw. A good method for bedding the M70, is to full length bed the rifle as I have done in the M700 video, but then make a pillar for the middle screw. This allows the tension to be brought up evenly on all three screws. But in lieu of this, loose middle screw tension will suffice. Winchester barrels are usually very good. The main concerns are: How true the action is and whether the action may need blue printing Middle screw tension Bedding Barrel as a final and constant consideration as with all rifle brands. |
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@ 06:07 am (GMT) |
Alvaro PiquerasRe: Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)Hi Nathan;Thanks a lot for your help! Let me tell you about the rifle. I have bedded it twice, because the stock bends under screw tension and contacts the barrel. After the second bedding process, with the “epoxy pillars” it seem to work well. I didn´t make the test you tell me, just because I put the action into the stock, and loctited the screws before I read it. Sorry, but I will keep this in mind. I´m so tired of working in that rifle, and want to start with the new load tests. But I can tell you that it semm to be without stress. The screws enter right, the action fits ok in the epoxy bed and it doesn´t seem to move during the tightening. The front screw is torqued at 40 inch/libs, the rear screw just a few less and the center screw, as you mention, slightly torqued and fixed. The rifle has a pair of weaver-style aluminum bases. I think I will go on with new steel ones, as I´m not sure if the aluminum bases will support the recoil of the 264. The rings are warne maxima, and the mount system it´s a bit missalingment, so I will lap the rings in order to mount the scope out of stress. Other option is mount a 20 MOA aluminum extended base. I don´t know if this will be necessary, because I don´t know if the Sightron SII Big Sky 6-24x42 will have enough elevation adjustments in his one inch tube (I have the one with mil-dot reticle, so this can be another advantage, but I think that dialing correction in the turrets will be better option, using the dot to estimate distances or for windage corrections). Sorry, Nathan, what do you mean with “blue printing” the action? Talking about loads, I hace notice that this rifle has a very big chamber. It´s hard to full-length size the fired brass, so I bougth a neck sizer die. I think it will be better to fire-form the brasses before look after a final load, as the resulting cases will have larger capacity. I think one of the keys with the accuracy and consistency of the load will be that. I will “waste” powder and bullets doing this, but will get longer case life (I have had cases broken near the belt, just where the sizing die stops). Anyone has opinion on Winchester LR magnum primers? This is the only brand available here (sometimes I can found sellier& bellot or CCI). CCI is the brand I like more, but it´s rare to see this in the shops. Thanks a lot! |
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@ 06:08 am (GMT) |
Alvaro PiquerasRe: Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)Sorry... i forget my cell phone at home, so i can´t send pictures now.I will mail the pics to you in a couple hours! Cheers! |
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@ 06:47 pm (GMT) |
Nathan FosterRe: Optimizing a 264 Win Mag Winchester M70 (with 24" sporter barrel)Blue printing involves setting the rifle action in a jig and re-machining all critical faces of the action square to the bore. The bolt is also trued during this process.Winchester primers will be fine. The fit of Winchester is slightly looser than Federal or CCI which can mean that if your run fairly hot loads (perhaps due to an accuracy sweet spot), as the primer pockets of the cases gradually open up, the Winchester primers will be a loose fit. But lets hope that you don't have to go down that path. The flexing you describe after bedding, occurs when the action is forced into the mortice under a poor fit. The action becomes stressed and begins to flex, the stock will also flex. The M70 plastic stocks are the most flexible stock on the market so if you have a plastic stock,you need to be extra careful. The poor fit could be because of dams being too high or high spots in the middle action area, perhaps just behind the magazine well. Flexing can also occur if the compound is too stiff and does not allow the action to settle naturally. Using G clamps during bedding will almost always cause stress, using the action screws can do the same. The short remedy is to use pillars as you have suggested. But ideally, you need to gradually learn to identify how you are inducing stress to the jobs. If you do not identify how you are initiating this stress, it will always be an uphill battle. No doubt you will soon recognize how it occurred. |
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