F-Class acceptable accuracy?

[spitfire_er]

I have been tossing around the idea of building an F-class rifle lately, but have a few heavy barreled custom hunting rifles that may get me "In the door". My one 7mm Mag will shoot 1/2" MOA at 100 with consistent regularity and in the 3's when everything is running good. Have not shot past 200 with it, but it's a shooter.

I was just wondering what type of accuracy do you guy consider competative. I have the itch, and will most likely build myself a F-class rifle this winter.

 

[Steve Blair]

A rifle that shoots a 1/2 MOA or better will be a good entry level gun provided it has the muzzle velocity to stay above 1.2 mach at 1000. Your 7 mag should do that with ease. That accuracy could win club level matches and shoot better than most. At higher competition levels, I think a consistent 1/4 MOA or better is needed.

In our Mid Range matches, the rifle must shoot much better than 1/4 MOA if you hope to win.

 

[Rustystud]

Steve:

My test of enough accuracy. Will your gun shoot a 10 shot group under .4" at 100 yards and will it hold 5." of elevation at 1000 yards.

A 7mm mag is a great round but may not be the ideal round and it is more expensive to shoot, (components and barrel life). It also is heavy on the recoil side and will take a toll on you physically in a day of shooting.
Nat Lambeth

 

[lal357]

i agree with the above i got hooked this year and was loaning out my 308 and 223 rifles so figured i would shoot my 330win mag in the open class(300yrd) shoulder only held up to 15rnds in prone position . so i told them to get thier own rifles.as for accuracy not sure good is needed i rebarreld my 308 with a shilen 30" match and got it down to .233 ctc 10shot groups @ 100 and hovering around 1" 10shot @ 300 yrds. i'm going to shoot that load and maybe play some more later as i have time .for me its when is time to just shoot instead of always testing this loador that load.

 

[Steve Blair]

A 7mm mag is a great round but may not be the ideal round and it is more expensive to shoot, (components and barrel life). It also is heavy on the recoil side and will take a toll on you physically in a day of shooting.
Nat Lambeth

Nat,

I am shooting a .284 Shehane that moves a 180 Hybrid at 2975. It does have a little recoil but at 21+ pounds, it is not that bad. You are correct, 7mm Mag would not be my first choice. But, if it is what the poster has, it will do the job to get his feet wet. If he is building a new rifle then I would recommend another cartridge.

Your point about vertical was also well taken. I should have mentioned that my match loads have velocity SD under 10, some well under.

 

[6BRinNZ]

That combo sounds plenty good enough to get you started. It would be worth trying 10 or 12 shot groups to see how it goes on a longer string...there is nothing worse than getting windage correct and dropping points due to vertical....be it the rifle or the load....

The other point that is important when starting out is; you refine your gear (reloading , rests, bags you name it...it all gets swapped once you start chasing points )as you go along, so even if your rifle isn't up to national standards, so long as it is consistent, you will be able to make good informed choices as you learn.

Good luck

 

[spitfire_er]

Thanks guys. That's kind of what I was thinking. I by no means expect to be the top shooter with my rifle, but it is always nice to have a chance. I know if everything falls together, I could win a match locally. I do have a 6.5-280 Imp. that shoots extremely well too, but it is a lighter rifle 11 lbs fully loaded and is set up more for hunting that target shooting.

I have personally built my last several rifles, but they have all been hunting rifles. I have been tossing around calibers and will ether settle on a straight .284, or some sort of 6.5, most likely not a 6.5-284. I like to be a little different. Don't plan on shooting past 600 with this rifle.

I do have a 7.62X54r target rifle that I built last winter, but have not had time to mess with load development. Also, I think it weights about 20 lbs. I can't remeber if there is a weight restriction or not, but I"ll check that out too. That rifle could be competative locally. My first couple groups out of it went just over 1/2" with undersized bullets, and no development.

Again thanks for the info guys. If I get a chance in the next couple weeks, I'll test my 7mm with 10 shot groups, and I'll set up the 10" gong at 600 and see what happens.

 

[Keith Glasscock]

Sorry for the late reply...

My theory is simple - if the rifle/ammo combination will hold the X ring vertically with a 7-10 shot group, you should not be dropping points to elevation.

Now there are some things that can bite one in the backside. First, your POI may shift some as the barrel warms. Most long rane shooters are aware of how their rifle moves the POI during a string and actively adjust for it. For example, my 308 slowly (and I mean slowly) moves the POI down on the target. It does this regardless of load and never really moves until the barrel starts to get warm. I just actively adjust my elevation by tracking the POI. If I were to shoot a 20 shot string without adjusting, I would have a group 1/4 to 3/8 MOA larger than the precision of the rifle.

So from my point of view, 1/2 MOA is adequate (at match distance - not 100 yards), but better is preferrable in order to ease group centering.

That is, until one reaches the shortest of mid-range. At 300, I wont shoot a load that gives anything bigger than 1" CTC (1.45" X ring) This is simply because 300 is a game of "11's". The match is almost always decided by X count. At 5 and 600, while cleans are somewhat common, the wind will get the better of people and you can easily win most days with the statistically probable X-count based on the percentage of the surface area that the x-ring covers.

Heck, I won the local 600 yard summer league last year (combined F/TR F-open, and Tactical rifles with muzzle brakes - ouch!) with 4 199's and a 197. Nobody shot clean. Maybe it was the concussion...

Another thought, reading through the previous replys... A lot of long-range shooters use velocity SD and ES to determine if their load will work at 1000 yards. We have to remember that chronograph numbers are only a (marginal) substitute for getting to shoot the real distance, not an altogether accurate prediction of performance. If I had the range available, I'd throw my chronograph away and shoot 1000 yards to test my loads.

Good luck, and go have some fun!

 

[DaveWhite]

I would add that you need to see how it performs in firing 20-shot strings plus sighters, fired quickly (<less than 10 minutes). Depending on barrel weight, you might find lighter barrels just not up to the task.

 

[spitfire_er]

Thanks guys. Both the 7 mag and the 7.62x54r are in the 0.9" muzzle dia, with straight tapers.

I have shot quite a bit over the chrony and have tracked heated barrel shots on a couple of my other rifles. My grandfather in-law is an old bench shooter and he also has a 1-300 yard range at his shop. He's a gunsmith too (wealth of knowledge). We also can shoot further, but need to set up targets. So I'm set there! I just need to go out and shoot.

I'm one of those guys that likes to know as much as possible before starting. I'm a fairly proficient shooter, but need to work on my wind game. I think I've got a good idea of what I want to put together, and all your replys keep me thinking.

 

[Steve Blair]

I would add that you need to see how it performs in firing 20-shot strings plus sighters, fired quickly (<less than 10 minutes). Depending on barrel weight, you might find lighter barrels just not up to the task.

Why less than 10 minutes, Dave? Twenty shots plus umlimited sighters is 30 minutes and 2 sighters is 22 minutes.

 

[Keith Glasscock]

I've been known to fire all 22 of mine in just about 7 mins (I've won that way more than a few times). I've even seen an F-open shooter win the match and set a new record shooting at that pace. While it is hard on barrels, knowing if the rifle can do it is helpful. Keeping the target in the pits is a valid technique under certain (uncertain?) circumstances. Sitting out a condition can work well especially if you can get all of your record rounds off while the condition is favorable.

I would second Dave's recommendation except I wouldn't do it with a magnum type rifle. It is just too hard on the barrel.

 

[Steve Blair]

The poster was talking about a rifle that he currently has and would like to use. It is likely not his ideal choice. He should get out and shoot it and see what happens. The 7 Mag does not need to be loaded to full power to shoot well and would have reduced barrel heating. My .284 Shehane pushes 180 Hybrids at 2975 from 32". Magnums don't do a whole lot better.

Regarding match strategy: the machine gun approach works in some conditions. I shoot matches at Camp Pendleton, 29 Palms MCB and Ben Avery. Occasionally, conditions are stable enough to do as you describe. We have a little wind down south here, too. Try your approach in a 12-16 mph, rapidly switching headwind (Pendleton), tailwind (Ben Avery) or swirling crosswind/tailwind (29 Palms). Most of the time, we take every shot for what it is. I've won a few matches that way, too.

 

[Keith Glasscock]

Steve,

I agree with you. There are days when slowing down and calling the wind for each shot is the only way to keep them out of the 7 ring (or worse). There are also days for the technique I describe. I've even shot in dead calm (more or less) conditions when pacing just doesn't seem to matter (except for barrel heating). I think we all need to have a full toolbox when it comes to dealing with the wind. I shoot on a 600 yard range at Tri County in OR where you sometimes never have to change your sight settings from the start of a string because changes happen so fast that you can't crank the knobs and get the shot off before it changes again. I've won in those conditions by taking my time and reading the mirage. There is nothing worse than winning a match with a score that you are embarassed to admit (188 - 3X) while besting your nearest rival by 7 points...

I wasn't inferring that the magnum should not be shot for F-Class. Instead I meant that I wouldn't try the machine gun approach with it. I theorize that the result of machine gunning a 7mm Rem Mag would be severe throat errosion and fire cracking. If I were to shoot a magnum in F-class, I would take a disciplined shot-to-shot wind call strategy. I simply think that any advantage machine gunning gives with the wind would be offset by lost accuracy as the barrel gets too hot.

I need to come down your way to shoot sometime. I think I could learn a lot from the weather conditions there.

 

[Steve Blair]

We would enjoy having you shoot with us. A good time might be the Berger SW LR Nationals in Phoenix, February 4-7. Phoenix is really nice in the winter. Another would be our Mid Range Regional Tournament, August 25-26 at Camp Pendleton. There are not many wives/girlfriends that would object to a winter break in Phoenix or a few summer days in San Diego. Come on down.

http://www.desertsharpshooters.com/
http://www.santamargaritagunclub.org/

 

[DaveWhite]

I would add that you need to see how it performs in firing 20-shot strings plus sighters, fired quickly (<less than 10 minutes). Depending on barrel weight, you might find lighter barrels just not up to the task.

Why less than 10 minutes, Dave? Twenty shots plus umlimited sighters is 30 minutes and 2 sighters is 22 minutes.

asked and answered - it would indeed be tough on a magnum, but conditions really favor those that finish their strings in as few changes as possible. that can be tough if you run out the clock...

 

[Steve Blair]

Dave,

I shot a .300 Win Mag and Sierra 220's in prone competition back in the eighties. The barrel got hot, it beat my shoulder, but it performed very well. The Obermeyer barrel went ~1400 rounds before dying. So, it did not have stellar barrel life, but it was not awful. Again, if it is what the poster has, it will do just fine to get started. Just because it is a "magnum" does not mean that it must be loaded to ear splitting levels. I loaded my .300 to ~2800 and it provided excellent accuracy, scoring 10's when I held well. Full disclosure: After the barrel went south, I sold the rifle and did not get another belted magnum.

Your conditions must be different that what we typically see. Your approach obviously works for you in your conditions or you would not use it.

 

[spitfire_er]

I guess I didn't think about firing that quick with a Magnum.. welll.... Guess I'll just have to build one then! Althought my rifle does have an exceptional accuracy node at 2850 fps.

I just decieded over the past few days that I'm going to build one over the winter. I'm thinking in the lines of ether a 6mmXC, a 6.5x55, or a straight .284. I'm still doing research, but I like the idea of any of the three. Will most likely do the 6XC or the .284. Not sure yet.

As a side note, I did measure up my 7.62X54r rifle. Barrel is 0.950" at the muzzle, weight of the rifle is 16 lbs without glass, but I'll have to shave down my 3.10" forearm to 3". Maybe I'll do a little shooting with this to see how it handles longer ranges.

 

[Jeffvn]

The 7Mag is not optimum, but it will certainly sling a 180 Berger at 2,900+ and if it truly holds 1/2 moa, it can be a heck of a learning rig. At distance, meaning 1,000 yards, the real key is a good load that holds a tight waterline (X-ring if you can find one). The wind pushes everyone around.

I would like to know where someone can shoot a 20-shot + F-Class relay in 7 minutes (averaging a shot in less than 20 seconds... not bad), and have someone in the pits pulling targets? Sounds like someone has automated targets to play with... I am VERY jeolous.

JeffVN

 

[Keith Glasscock]

Nope, nothing automatic. We just have really good paid pullers. If you don't shoot too many 9's it is a bit easier - the puller doesn't have to move the paddle much.

One thing that will ruin it is smacking the spindle. It takes a full minute to repair after that ;D