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38superman

I don't know how the military does it with the .308

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I know the military produced many fine snipers armed wht the M40 and M24.

It is also obvious that there are many tack driving .308s in the world.

That said, my Hvy Barrel M700 is driving me to drinking.

I have been shooting groups and doing my due diligence with load development.

The rifle shows flashes of greatness and potential.

It often shoots 1/2 moa 5 shot groups. Just as often it shoots 1 to 1 1/4" groups.

Many times I have put 4 in one ragged hole only to have the group ruined by a flyer that more than doubled the size of the group.

If you took the average of all the groups fired it would be somewhere between .8 to .9 inches.

In short, the guns is capable but not consistent.

I'm sure I can improve it with a better trigger, and I would like to play about with the seating depth.

However,.....

It was my intent to put it in a chassis and turn it into a magazine fed competitor for precision rifle matches.

For that reason, I have been loading to mazagine length OAL. (2.810" max).

When loaded to that depth, the throat is long enough to have bullet freebore more that 200 thousanths.

I could seat it out another 080 and still run in an Accuracy International magazine, but thats still more bullet jump than I would like.

Even if I were willing to load it single shot, a bullet seated anywhere near the lands is barely in the neck with all but the heaviest bullets.

Go really heavy and the bullet has the trajectory of a mortar round.

Maybe a custom chamber Palma throated barrel is the answer. Don't know.

Suggestions?

Edited by 38superman

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Uncle Sam uses M24/M40 with M118LR because it simply works, and gives a good value to us tax payers, with that said unless your shooting against others who are using 308 Winchester chambered rifles you'll get your butt kicked by someone shooting a 6 or 6.5mm cartridge, keep shooting the 308, but save your pennies for a new rifle with a custom chambered barrel in a cartridge with a 30 degree shoulder like a Creedmoor or Lapua in either 6 or 6.5mm

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I am having two of my 700 actions re barreled in 6.5 Creedmoor for that reason. It is like running into a wall and getting up and doing it again trying to make a .308 competitive with the 6 mms.

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Military rifles use a chamber throat specifically designed for the M118LR, and no concessions were made to allow the use of round-nose bullets. That said, your bullet jump sounds excessive in the extreme, even for a multi- use factory chamber. What bullet weights/ styles are you trying? Sounds like a setback/ re-chamber or a new barrel is in order to me. The .308 is a very inherently accurate cartridge. A world-class shooter with a .308 can keep right up with the 6.5mm guys. Benefits of the smaller calibers are primarily in reducing compensation errors due to higher BCs and velocity, which makes for flatter trajectories and reduced wind drift at slightly less recoil. Result? A more forgiving system if you mis-calculate, with less gun handling technique required. Do your corrections accurately and the .308 will put bullets where they need to go.

Biggest mis-conception about military snipers? They are shooting at bigger targets than people think. Snipers are more than OK with most torso hits, and will gladly take a leg hit on a towelhead if it reduces the engagement. A 12w x 26h target is more than 1MOA even at 1,000 yds. Solid hits on fleeting targets are WAY more the rule in combat than through-the-scope eyeball shots at stationary enemy snipers like the movies show. A military sniper would much prefer a rifle that ALWAYS shoots 1MOA, hot or cold, clean or fouled, bipod or backpack over a 2 week deployment rather than a 1/2 minute rifle that has to be coddled or it throws 3 minute groups from time to time. Totally different situation than the type of matches you want to shoot. 6.5 or 6mm might be your best choice for what you are doing. Not necessarily for them.

Edited by openclassterror

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I recognize that a 6 or 6.5 mm might be better suited for Precision Rifle.

That's not really the issue. I am still in learning mode having only shot one such match to date.

At this point it wouldn't matter what blaster I show up with, I will not scare the elite shooters,..... yet.

Last fall I showed up with a .223 and a ballistics calculator for my first match.

I was not well prepared as the .223 had never fired a shot beyond 100 yds and I didn't have enough of my pet load so I had to shoot factory ammo.

I scored about 52% of the winners score. Nothing to write home about but a decent first effort. Was getting solid hits out to about 550.

The issue now is to get the .308 shooting more consistently. It may not match the more exotic calibers but should be a step up from the AR.

My best load to date is 44.5 Varget behind a Nosler 168 Custom Competition bullet.

That load at magazine length is a pretty consistent 3/4 MOA performer but only produces about 2600 fps from my 26" barrel.

I bought some 155 SMK Palmas to try. They have a high B.C. and my hope was that I could find an accurate load that would push the lighter bullet to 2900-3000.

The problem is that high B.C. comes at a price. At 2.800 OAL, the long slender ogive doesnt touch the lands until it moves .210 thou.

I shouldn't be a pessimist before I send a single one down range but that's just too much freebore. I will be very surprised if it performs as hoped.

The gun desperately needs a better trigger (Timney maybe?) but I don't have the tools or experience to do it myself and I'm not sure who to trust with it.

Tls

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Your 168 load info is a puzzler. I use 42.0 gr of Varget behind Hornady 168 HPBTs and get 2630 out of a 24" barrel. Federal Commercial .308 brass, not military thick-wall stuff. Oddly, from 40.5 to 42.5 there was only a 50fps avg velocity increase. I think that 26" might be beyond the effective burn rate of the powder choice. Have you considered trying a slightly slower powder to get better performance out of the 168s, or going to 175s? With the right load and the BC of a heavy bullet you may find that the 175 trajectory is VERY close to your 168s. You should have no trouble getting 175s out your barrel at 2600+ if you go to a powder better suited to your barrel length. With less jump than the 155s :)

Timneys are a drop in unit, you don't have to be a gun guru to install. The JP EZ is a good compromise, about $100 bucks, come with a GOOD set of instructions AND a DVD! Not beyond the ability level of anyone who can make good handloads. JP kit, and bob the factory hammer and you are good to go! JPs tech guys are also very helpful on the phone should you have questions as you go.

Edited by openclassterror

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You could have the barrel set back and the chamber recut - about the only way to get to a shorter throat short of a new tube. That said - it may not improve your performance.

Rem barrels in Rem stocks with Rem triggers are a nice stacking of tolerances to give you what you are seeing. I did what you are doing - put an SPS-V into an AICS stock with a nice trigger - and it worked pretty well. I used 155s with a healthy jump (Lapua and Nosler CC) but it really preferred the 185gr Berger VLD in a single shot configuration. Plenty of bullet in the case and it liked a .020 jump the best. Even so - it took 10-15 rounds to 'settle' the barrel after cleaning and I would occasionally have some weird POI shifts and the odd flier in to the 7 or 8 ring (F T/R) Some of those might have been me :)

I dumped it in favor of a 30" Krieger 1-10 heavy palma with a Palma 95 chamber + some extra throat to give me the case capacity to shoot the 208gr Amax or the 185gr Berger VLD. Mortar like? The 185 is humming along at 2850ish fps using MR2000 for a 1.1 mil drop at 300 and about 3.5ish at 600. 208 loads have been between 2400fps and 2700ish fps - not a bad deal - with the faster loads being within .1 or .2 mil of the 185s at 300 and 600. Google Montana Marine and 208 Amax for info RL 17 and the heavy bullets in .308

Regardless - with the Krieger barrel I have done away with the weird POI shifts and now the fliers seem to be greatly reduced - in other words, they seem to be my fault, not the rifle.

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28 years of shooting the 308 and I recently went to the 155 gr Palma bullets. I shot 168gr all these year and lots of M118Lr. It is capable of competing. I am thinking of going to the 6.5 Creedmore for my next rifle. Better BC and less recoil.

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Just so happens I have a 308 savage I have been practicing with for my first PR match coming up in Aug.

I was getting groups like you discussed, 3-4 shots touching or almost one hole and a flyer or two.

After much reading and watching the SnipersHide online videos I now think I am the weak link; NPA, body position, recoil management, follow-through.

I don't know what your rifle shooting experience is besides what you stated. I have some 3-gun experience, 10" MGMs out to 400yds or so and while not anywhere near a great pistol shooter (SSP MA) I do have some abilities but my precision shooting skills apparently leave a lot to be desired.

Just asking, do you shoot other rifles better than this one?

If so, then OK it's the rifle/load. If not?

David E.

Maybe ROB O. Team Blaster will chime in. Knows more about 308 PR than????

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I've never shot benchrest until just this past weekend, but I have been shooting groups for load development for 40 years. I am a respectable handgun competitor having shot in USPSA since 2004.

Could the problem be the loose nut behind the trigger? Sure it's possible. I have found over the years that my grip , breathing, eyesight, trigger control etc. is good enough to shoot 1/4 inch groups if the gun and load will support it. That's about the limit of my skill set. However, give me a 40x scope on a custom built BR gun with a 2 ounce trigger and I can do it all day.

Anything is possible, but I can't think that the same sight picture, and technique that puts 4 in a ragged hole suddenly lapses into a 2 inch flyer unless something went terribly wrong with the gun or the load.

TLS

Sent from my DROID RAZR HD using Tapatalk

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"same sight picture, and technique that puts 4 in a ragged hole suddenly lapses into a 2 inch flyer unless something went terribly wrong with the gun or the load.

On the same token looking at it from a mechanical perspective, if all your rounds are mechanically the same the result should be a given accuracy (.5 MOA, 1.0 MOA, 1.5 MOA or 5 MOA) not 4 great (.5 MOA) and one/two flyers.

If you verify all your loads are equally produced the result should be consistent/equal, be it good or bad.

There is much discussion about the 1 MOA all day long but for that one flyer and the cause of that one flyer.

In any case, it sounds like you are ahead of me in the Precision Rifle game.

Good Luck!

David E.

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You make a good point Dave. If the mechanics are the same, the results should be consistent. The shooter is always suspect and I'm sure some of my wounds are self inflicted.

That said,.....

the only way to get consistent mechanical results is to minimize the variables to absolute 0. Commercial brass is good but not perfect. Neck thickness varies, flash holes vary, wall thickness changes as brass weights (even within the same lot) will deviate several grains. Bullet weights, diameters, jacket lengths are ever changing.

A perfect chamber and barrel can absorb a lot of these tolerances in the ammo and still produce tight groups. In a production gun these things stack up and conspire against you. A lot of those issues can be eliminated if you want to go to extremes with your ammo. I guess I'm just too lazy to weigh bullets and turn necks. Even if I did all that I still would have to contend with the long throat this particular rifle was minted with.

Good Luck.

TLS

Sent from my DROID RAZR HD using Tapatalk

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The source of my frustration. Seen below are some of the 3 shot groups I made while trying to find a working max with Varget.

post-6467-0-81111300-1403646192_thumb.jppost-6467-0-22873400-1403646293_thumb.jppost-6467-0-24654000-1403647656_thumb.jp

Yes that first picture is indeed 3 shots. :cheers:

When I find a promising load I shoot five shot groups to prove it out. I got a few of those that were good enough to tease me.

Just too many like this:

post-6467-0-55906500-1403647066_thumb.jppost-6467-0-73290300-1403647090_thumb.jp

Edited by 38superman

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My rem 700 5R had three miles of jump when running maglength rounds out of AI mags (badger dbm installed by a local smith).

175SMKs tolerated the jump and still ended up shooting pretty much to the limit of my ability to hold and windread at 1K.

You've been shooting long enough to know to work up. My load for my 700 5r turned out to be 44.1gr varget, 175smk, wolf primer, fed brass with a 336 bushing in the redding full length sizer. Seated to avg oal of 2.816.

If you're sure its not your hold or breathing, perhaps time to bed the action?

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needles to say I have shot lots and lots of .308 and other calibers at and past 1000 yds with great success. I will be the first to tell you that Army sniper rifles are not effective past 800M. the Specs were simply not there with the M-24 and M118. M118 LR preformed much better but many of the rifles were simply not capable of the accuracy required. The New SASWS also runs out of gas at close to 800M or so due to the shorter barrel and velocity of M118LR when shot out of it. There are lots of variables that play into this. I can tell you for a fact that the degradation of marginal ammunition from 800 to 900 and 900 to 1000 is significant. If your on the ragged edge of staying supersonic at 800 or so, things start to fall apart at 900 and the wheels will come off at 1000.

I would suggest that a 3 round will not give you much information at all. Shooting a single 10 rd group will give you a much better potential of your rifles capability. I don't know much about your rifle but many of the factory HV rifles are closer to 1-1.5 MOA at best for 10 shot groups. Experience tells me that most posts of .25 groups from factory guns is simply not the case, sure it might happen once but not consistently.

There are a few things you can do that might help: Skim bed the rifle. take the action out and bed it into the aluminum action block. On many of these factory guns the actions are not all that well fitted to the stock and things are shifting around. Other things to check is the parallax on your scope, last is cronographing your ammunition. Without getting too much into it, if your velocities are erratic and your ES and SD is high, these are indicators of a combination that's not working well together; it does not tell you exactly what you need to change, but its an indicator that things are not happy inside your case. The effect is erratic harmonics on the barrel and bullet.

With all this said 40-42g RL15 or VARGET or H4895 with 168's or 175's should shoot well provided you do your part. If they don't group at 100 or 200 yds then its likely the bedding or you need a better barrel, and again expect 1-1.5 MOA at 100 Yds or so. Oh yea, most every LR shooter that I know is happy to get a 10 shot 1" group at 100 with low ES and SD and its tougher to get then you think with 2000+ custom target rifles.

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needles to say I have shot lots and lots of .308 and other calibers at and past 1000 yds with great success. I will be the first to tell you that Army sniper rifles are not effective past 800M. the Specs were simply not there with the M-24 and M118. M118 LR preformed much better but many of the rifles were simply not capable of the accuracy required. The New SASWS also runs out of gas at close to 800M or so due to the shorter barrel and velocity of M118LR when shot out of it. There are lots of variables that play into this. I can tell you for a fact that the degradation of marginal ammunition from 800 to 900 and 900 to 1000 is significant. If your on the ragged edge of staying supersonic at 800 or so, things start to fall apart at 900 and the wheels will come off at 1000.

I would suggest that a 3 round will not give you much information at all. Shooting a single 10 rd group will give you a much better potential of your rifles capability. I don't know much about your rifle but many of the factory HV rifles are closer to 1-1.5 MOA at best for 10 shot groups. Experience tells me that most posts of .25 groups from factory guns is simply not the case, sure it might happen once but not consistently.

There are a few things you can do that might help: Skim bed the rifle. take the action out and bed it into the aluminum action block. On many of these factory guns the actions are not all that well fitted to the stock and things are shifting around. Other things to check is the parallax on your scope, last is cronographing your ammunition. Without getting too much into it, if your velocities are erratic and your ES and SD is high, these are indicators of a combination that's not working well together; it does not tell you exactly what you need to change, but its an indicator that things are not happy inside your case. The effect is erratic harmonics on the barrel and bullet.

With all this said 40-42g RL15 or VARGET or H4895 with 168's or 175's should shoot well provided you do your part. If they don't group at 100 or 200 yds then its likely the bedding or you need a better barrel, and again expect 1-1.5 MOA at 100 Yds or so. Oh yea, most every LR shooter that I know is happy to get a 10 shot 1" group at 100 with low ES and SD and its tougher to get then you think with 2000+ custom target rifles.

I am hoisting the bullshit flag.

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if your saying that your rile is capable of shooting really good groups "sometimes" your problem is you...not the rifle.

sorry :(

barrels are either accurate or inaccurate based on your skill to load/send rounds....there is no such thing as "somestimes accurate"

Edited by jriggs

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jriggs,

So it is your position that if there are inconsistent results in groups, it can only be the shooter.

No other possibility exists?

In a machine rest with the human element removed no anomaly is possible.

Groups will always be the same

You will never see a flyer.

Edited by 38superman

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I didn't see anything glaring in dauntedfuture's post - I'm a Palma shooter (among other things) and can confirm that the 308 starts to get increasingly wobbly past 800 yards.

The factory Rem barrels are typically throated very long, necessitating the use of a jump-tolerant bullet (Sierra 175s, others) or a set back and rechamber job. Both work. Cryoing a factory barrel that's shot for long strings is often useful to alleviate "walking" as the barrel heats or cools. Bedding may need a look too.

Other'n those things, it's your position. There are many, many more ways to dork a shot with muscle tension, NPA and whatnot than by purely mechanical means.

Mark

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So even though I said I was new to this game, looks like I'm not fare off from "dauntedfuture" and "redial".

38 superman, your post about being able to shoot 1/4" groups all day long with a bench rest gun with a 2 oz trigger after shooting BR for the first time in your life last weekend is still stuck in my throat. If that's the case you should take up F class as I think you would be killing those fellas.

All in good fun,

David E.(new guy to long range 308)

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Nuke,

Sorry man. I didn't mean to choke you.

Maybe I was overreaching a bit, but the point I was trying to make is that I'm an excellent marksman and experienced enough to call my shots off a bench rest.

If my gun / load is misbehaving or if I'm just having a crappy day or if the wind is messing with me I can tell the difference.

I am not an experienced benchrest competitor but having shot with the local club, it was clear that consistent 1/4 inch groups at 100 yds. is what it takes to be competitive.

IIRC, The match winner that day had an aggregate score of .179

As several shooters have loaned me their guns I found that I could hang with them with the right equipment.

I don't read wind as well as they do but put up some very respectable scores.

Everyone that has posted on this thread had good points to make and suggestions.

I think I made a mistake by trying to go to lighter bullets because my velocity with the 168's wasn't where I expected it to be.

I should have been more patient and worked with some slower powders instead of lighter bullets.

My feeling at this point is to start working with the 175 / 185 Sierras and Bergers and see if I can get them to shoot at mag length.

I still have plans to put the barreled action in a McRees Precision chassis and add a Timney trigger.

I will shoot the gun until it is time to rebarrel it and possibly go to a .260 or simliar caliber, but I haven't given up on this particular rifle just yet.

I firmly believe the .308 can do better and so can I. I won't stop until I get plumb potential from the gun and the guy behind the trigger.

Tls

Edited by 38superman

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Tis,

I am really new to precision shooting and "precision" reloading.

I threw the F class thing out there but had no idea .179 was possible so I must be off the mark with accuracy expectations.

I shot a few rounds through a friends gun (Rob O.) the other day. I think maybe I had a shotgun pattern but still 1 MOA at 100yards which is normally better that I shoot with my gun.

So then he shoots a few rounds and has basically one hole.

It was then I realized I couldn't shoot well enough to even zero his gun and most likely my gun either.

I hope you find the right combination for your setup.

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jriggs,

So it is your position that if there are inconsistent results in groups, it can only be the shooter.

No other possibility exists?

In a machine rest with the human element removed no anomaly is possible.

Groups will always be the same

You will never see a flyer.

What I'm stating is:

Inconsistent results = yes could be a lot of other things that the shooter.

But if someone is getting really good groups "some of the time" then it's most likely pilot error.

Yes there might be a problem with harmonics or something like that but that doesn't create flyers like described above. I've watched BR shooters shim barrels with paper to balance harmonics and stop flyers but were talking fractions of an inch at 100 yards

Sometimes it's not easy to admit but not all of us are great at pulling triggers. I know I can shoot decently at distance... But I've watched guys squeeze so much more accuracy out of my rifle than I ever thought possible (shooting my rifle, my ammo off the same rest) and the only difference during that lesson was the shooter.

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Regarding shooting .308 at 1000, if you go the route of a factory rifle, and its a great way to start; the 168's are not a good bullet for 1000, go with the 175's. if your rifle will shoot them. Many of the factory .308 are 1-12 twist which might shoot 175's at 1000. You can also try the 155 palma bullets as they will usually shoot well in 1-10 to 1-13 barrels. Check your velocities and make sure you are over 1200 FPS when you get to 1000. .260 or most any of the 6.5's make great 1000 yd guns, 6.5x .284 still dominates NRA LR competition as far as I know. Its easier to get 3000 fps with 142's than .260 and with less pressure. Barrel wear is close. you would be loosing a little with a 6.5 creedmore at 1K but it will still work well with less recoil.

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