I need some advice. I have an older Remington 700 that I am having rebarreled.
After dropping off the parts and discussing what I wanted to do, I realized that I don't know enough about chambers to know what to ask for. Having only shot factory barrels, I only know how to work with what I have but don't know what I want.
As stated above, the action is a '84 Remington 700 chambered in .308. I am not changing calibers. The barreled action will be mounted in a MDT TAC21 Chassis and I will use it for long range shooting at 1000 yards. I'd like to load to magazine length, 2.84", but, if that is a detriment to accuracy it is not a requirement. I have been shooting 175 gr. SMKs and TMKs and experimenting with 178 gr. Hornady ELD-Xs. I also have some Nossler 175 gr. RDFs.
This is not a competition rifle as I am not engaged in any competitive shooting endeavors.
What would you suggest I request of the shop with regards to chamber and other aspects that I am likely unaware of?
The new barrel will be 24" and will have a 1/10 twist. The barrel brand is Rock Creek.
The action is being trued.
Thank you for your help,
Factory 700 .308 barrels have really long throats in their chambers, long enough that you can't seat a bullet out to the lands and still have it far enough into the case neck to keep it stable. Be sure to talk to your smith about it and have him cut the throat appropriately for the range of bullet lengths (which do NOT necessarily correlate to bullet weight) that you plan on using.
Besides doping wind conditions (which is a skill that requires many many rounds of practice) and a fundamentally accurate barrel and load, one of the big keys to success at long range is keeping the bullet supersonic all the way to the target. A 175 or heavier bullet in a .308 will do it as long as you launch it with a sufficient velocity. Duh. Sounds like a pretty obvious thing, but some factory ammo isn't loaded hot enough to stay supersonic out to 1000 yards. If you're handloading, which it sounds like you are, you have a lot more flexibility in bullet and powder selection, charge weight and seating depth, all of which factor into muzzle velocity.
If you're not dead set on sticking with .308, you might consider something like a 7mm-08, 6.5mm-08, or 6.5CM. It would give you equivalent or better ballistics with somewhat less recoil (140 or 150gr bullet vs. 175-185gr). The 6.5CM is also a slightly shorter case, which would allow you to seat your bullets out a little further (maximizing use of case capacity) and still be able to feed from the magazine.
If you are having it custom chambered, then you can have the throat anyway you like. Give your riflesmith a dummy round with the 175gr SMK loaded to the OAL you want, then ask for 0.010" lead in the throat. Some of the other rifle guys will chime in, but there are also min SAAMI specs for chambering. With some brass that may require neck reaming.
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Do what fredj338 suggested, give your gunsmith a dummy round with how you want the bullet seated. Bottom of the boat tail slightly above the neck/shoulder junction is common practice. I recently did the same on two Dashers barrels I just had chambered. FYI .004 neck clearance has worked well on every caliber I've had chambered. With the MDT chassis you can obviously use AICS mags. The AICS front plate can be drilled out and removed for a OAL of 2.98, might change how your dummy round is set up. I've removed the front plate on AICS mags, works great, no problems. Have fun!
The dummy round thing is what I do also, but since I use VLDs, I ask for the bullet maximum diameter to be right at the lands.
Also, I can't help but think that if you're building this rifle specifically for LR shooting to 1000 yards, you would be doing yourself a favor by increasing the barrel length to 26 inches or maybe even 28 inches. The bullets you plan to use are not the greatest in terms of long range performance, by any stretch of the imagination, so you should have as much barrel as you can get. If later on you decide the barrel is too long, you can have it cut down and recrowned, but you can't add to a barrel.
Also, what contour are you looking at for the barrel?
+1 for the comments on dummy rounds. My latest barrel's chamber was cut for a specific round and it shoots great.
I don't have all that much experience with TMK ammo -- maybe 3 boxes each of 168 & 175 from Black Hills. IMO the TMK bullets didn't play well with a chamber that works well with SMK ammo. I've seen on other forums that the TMK bullets don't tolerate jump very well, and that the SMK bullets do tolerate fairly generous amounts of jump.
Thus, I suspect sticking to one bullet and having the chamber cut around that bullet, will produce the best results.
IF you go longer barrel, go heavier too. My buddy has a F class savage, 30" bbl, You can literally see the barrel vibrate with each shot, like a tuning fork. it is his most finicky rifle for accuracy. My precision rifle is a 26" heavy in 260ai.
IF YOU AREN'T HANDLOADING, YOU AREN'T SHOOTING ENOUGH!
NRA Instruc: Basic Pistol & Met Reloading
I think if you see the barrel of a Savage vibrate, you're either having visions or the action is not bedded properly.
I have several friends who have Savage F-Class rifles, F-Open and F-TR and I have never heard of or seen that.
The usual contour for a target rifle or an F-TR rifle will be some manner of Palma contour. My F-TR rifle sports Heavy Palma contour barrels. They do not vibrate even at 34 inches long.
Thank you all. I have made an appointment with the shop to bring in some dummy rounds and discuss these issues.
I am a little worried that I could make things worse by not really knowing what I am talking about but hope to get some guidance from them.
Thank you all again,
As others have mentioned it depends on what bullet you decide to shoot. Bullets with smaller bearing surfaces will require less freebore to minimize jump. I've found the new Nosler RDF and Hornday ELD series to be jump tolerant and shoot very accurately out of my 6.5 CM. I always have my 6.5 CM barrels chambered to shoot the 140 ELD M. I don't bother with the Berger Hybrids, Lapua Scenars or VLDs as they are difficult to source reliably.
I guess in a long winded way I'm saying pick a match grade bullet that is easy to source and ask your smith what he recommends as far as freebore.
I have the rifle with the new barrel and I plan to take it back.
Some if this is my issue and not the gunsmith but I want some follow up advice. As a refresher, this is a Remington 700 chambered in .308 with a 26" barrel.
The problem is that I am trying to load some longer projectiles like Berger 185 Hybrid Target and 185 Juggernauts. The lands are so close that the OAL is 2.81 with the Hybrid Targets with the projectile on the lands! There is so much bullet in the case that I can't get any powder in it.
Even 175 RDFs are at 2.80 when touching the lands.
I am not planning on running any short or light bullets in the gun. It feels like I need at least .15" more distance to the lands to make space for powder.
How do you know what to ask for? I don't mind running bullets into or on the lands but I prefer not to if the bullet will shoot without doing so.
I think the competitors here may have it easier with this question as you likely only run one projectile and have a really good idea where you want to run it off the lands which will determine the OAL.
I can only commit to a projectile when I know what the barrel will shoot well right?
As always, thanks for sharing your experience and advice.
As mentioned by previous members, you need to take a dummy round with the bullet you intend to use and seated to the depth you want to your gunsmith. He can use a throating reamer to adjust/lengthen the freebore for your needs. It would be helpful if you have an idea of what kind of distance you want to the lands, if any, so he can allow for that as well. Another thing to consider is throat erosion. If using a bullet that needs to be kept close to the lands with minimal jump to maintain accuracy, give consideration to seating depth to allow for the increase you may need later in the barrel’s life. If you are going to be feeding from a magazine, consider overall length, now and in the future, to make sure the rounds will fit your magazines. If single feeding, OAL is moot as long as you have enough bullet left in the case if chasing the lands as the throat erodes.
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I have nothing to add to what Sig Marine said; he covered it well.
Instead, I will answer the last question from the OP.
Why not? In my experience, a good barrel will shoot most anything properly. If you have read my sticked thread here, you will have noticed that I selected the bullet I wanted to use PRIOR to getting the barrel chambered. As Sig Marine pointed out, I fashioned a cartridge the way I wanted it assembled for COAL, powder capacity and bullet heel seating using the bullet that I wanted to use.
I did that with the 180gr JLKLBT and then again a couple years later with the 210gr JLKLBT. Experience with VLD designs guided me to have the bullet seated right at the lands. I seat further out over time until I swap out the barrel.
In your case, since you are using a non-VLD design, it's better to seat short of the lands probably at about 0.20 or so, but you can certainly ask for a little more freebore from the GS to allow you to play with the length.
I like to have my bullet seated in the case so that the pressure ring is just underneath where the shoulder meets the neck. I start a little more under and over time, it comes closer to the junction.
The long boat tail design actually forces the powder to be all around the tail, but the load is not compressed and the powder does not move; two qualities I like in a handload.
Thank you Sig Marine and NikonUser. Sounds pretty simple and intuitive now that you've said it.
As I said earlier, Sig Marine did a great job. I just babbled on.
The thing of it is, lots of forum denizens like to perpetuate the canard that all barrels are "a law onto themselves," or better yet "all barrels are different."
If that were the case, there would be no decent ammunition out there. Our friend fritz constantly reminds us that he gets great results from premium match ammo, notable FGMM and similar. He's not just blowing smoke; it's true. If that wasn't the case, the only way you could get good accuracy from any of your rifles would be by going through the lengthy process of trying out various combinations of powder, bullet, primers and assembly specs for each and every rifle you own.
Obviously, that's not needed because the vast majority of shooters don't handload and of those who do, very few go much beyond book specs with whatever component they have on hand or can buy cheap.
It takes work and handloading skills to match the performance of factory ammo, and even more so to match the performance of premium or match factory ammo.
And that factory ammo is made up of a load that works in a rather large array of different barrels.
It's the same thing with the bullet from Berger, JLK, Sierra and others. Provided the twist is adequate, these bullets will fly out of your barrel and fly very well. Assuming that you have the proper handloading skills, of course.
So, pick the bullet that you want, make sure your twist is adequate and then do your deed.
I am not sure I am in 100% agreement with you. I often shoot FGGM in .308 or one of the Hornady Match loads in 6.5 Creedmoor in the early stages of load development just to see what results "known good" ammo will yield.
Perhaps wrongly, I want to see an indication of what the barrel is capable of. If it won't shoot that stuff to less than 1 MOA then something is off--could be me.
The important part of that idea is "known good" but, that is not saying known great or known close-to-perfect.
I have a Thompson/Center hunting rifle that shoots 165 Sierra GameKings into a very small group of between .5 and .8. I don't load for that rifle because that is more than enough accuracy for the area I hunt, with a maximum range shot of 300 yards. 1.5 to 2.4 inches makes no difference for that purpose. Okay, for full disclosure, I did develop a 168 Berger Classic Hunter load that does just as well and maybe a little better.
If factory ammo gives you all the accuracy you need and you have great faith in its consistency and you don't mind ordering it, storing all that you will need for times of shortages and paying the ridiculous hazmat fees then you're good but; while going to the expense of purchasing and fitting a top tier barrel and running only factory ammo may meet your needs it seems to me like that is analogous to running low octane fuel in your racecar that was designed to take advantage of racing fuel. If you are winning races who cares, I suppose, but I'd go crazy not knowing the full potential of that rececar or barrel (personality flaw?).
That is not meant to be judgmental. Some folks spend all their time and energy looking for the perfect load and once they have it or close to it, they are off to a different project. Some people shoot very high volumes of good-enough ammo and some people just collect firearms that they will never shoot. We are all in a similar orbit and there is something to learn from everyone.
P.S. I know Fritz is going to tell me how wrong I am and that's okay. I admit that I like to hand load and it is part of the enjoyment of the sport for me. Plus, I have learned about (from you, mostly) and acquired several amazing tools that take almost all of the drudgery out of case prep and vastly speed up accurate powder throwing.
In times of panics, ammo shortages were little different than certain reloading component shortages – especially powder. I’ve never paid a hazmat fee to ship any loaded ammo, even when shipping 1,000 to 2,000 rounds at a time. Nor have I done business with any company that charges hazmat for ammo, as ammo only requires the ORM-D shipping label. Now hazmat fees for powder are quite common – but I don’t have to pay them.
Let’s consider your racecar analogy. IMO you don’t have a racecar. A trued Remy action can be quite good – but it’s not in the league of Big Horn, Defiance, Surgeon, or AI actions. Furthermore, your action is a repeater. The true “racecar” actions in benchrest and F-Class tend to be single loaders. This means Big Horn, Defiance, et al are more akin to souped up SUVs.
Your 24” barrel is definitely on the short end for 1,000 yard targets with a 308 at low elevation. Barrel length of 28-32” would be more appropriate, assuming you wish to have velocity above transonic at the target.
I feel my 3 Bartlein and 1 Kreiger barrels work just fine with factory ammo. I don’t shoot very many groups once the scope is zeroed and ammo is sampled, but I do keep records of what my rifles like. The four best 5-round groups at 100 yards from my competition rifles with my derp trigger skilz are:
6.5 Creedmoor -- .198” .28” .33” .36”
308 -- .23” .32” .33” .35”
20” AR-15 -- .32” .34” .55” .55”
I’ve shot the 6.5 out to 1800 yards, the 308 out to 1400 yards, and the AR out to 900 yards. They all hold vertical well with factory ammo out to velocities of roughly Mach 1.2, sometimes even lower. With Hornady, Federal, and Corbon ammo. No engine knocking with this octane.
I know a little of the Berger 185s, as I’ve shot ABM ammo loaded with them. I had to single feed the ammo, as it was too long to fit in my AICS mags.
Your chassis isn’t a “racecar”, in the way bench & F-Class stocks are. Consider their solid-bottomed stocks, which assist in using a sand- or lead-shot filled bunny-eared rear bag to control the rifle’s elevation and direction. The MDT chasis looks more optimized for steel/precision/tactical type matches, which makes it akin to an off-road SUV.
If you have Harris or Atlas on that rifle – more SUV. The “racecar” bipod will be something really wide – like a Sinclair or Phoenix Precision or SEB. Maybe something I have no clue about.
How about optics? “Racecars” will be sporting ED glass with magnification topping out at 50x or more. Top end magnification of 25 to 30-ish power? That’s an SUV or sports sedan.
If you really wanted a “racecar” precision rifle, you probably shouldn’t have it chambered in 308. Sure, 308 ammo is pretty easy to tune. There are lots of quality bullets available. But 308 rifles generally only perform well in competitions which limit the field to other 308s. There are less energetic chamberings than 308 which buck the wind better, shoot flatter, have less recoil, and shoot more accurately than a 308. Or there are more energetic chambers which have ballistic advantages at longer ranges. And yes, I know, because I’ve shot a few of them.
Striving for the great accuracy is a worthy goal. But accuracy isn’t only what the action/barrel/bullet can do. We humans must aim the rifle, press the trigger, and control the rifle through its recoil cycle. Well, control isn’t necessary if you’re shooting a rail gun or using free recoil methods. But maybe you can develop a round that shoots 1/2 MOA at 1,000 yards (roughly 5”). Maybe even 1/4 MOA. Can you hold 5” or less of vertical & horizontal at that distance? Or how about your wind calling ability? Maybe your uber 308 round gets deflected only 7 MOA at 1,000 yards in a 10 mph wind. To keep lateral POI within your bullet’s 1/2 MOA accuracy, you must consistently call wind within about 3/4 of a mile per hour. That’s a big challenge.
It’s your choice – fiddle with ammo to the nth degree, or develop good enough ammo and develop shooting skills. You may ultimately find that so-called high octane fuel doesn’t make any practical difference to how fast that SUV gets from point A to point B. But your skills behind the wheel (trigger) definitely make a difference.
Sorry I was so late to the party. I try to stay away from computers on weekend, the honeydo list was long this weekend. Add to that a 1000 yard match on Sunday and then I had to go out of town for the week. I'm on site now, and with some time to catch up.
I think I failed to get my point across which was that while lots of people navigate under the misapprehension that all barrels are totally unique and react completely differently from any other exact same barrel, and there is no way to predict how they will do with any bullet, well, I just don't agree with that outlook on rifle life.
Furthermore, it was not my intention to dissuade anyone from handloading for their own rifle to extract every last possible bit of precision. In fact, the reason I handload for my match rifle is twofold; first is to use the exact bullet I wanted to use and second because I believe that I can do a better job developing, tuning and consistently load a better cartridge than store bought ammo.
My point was that in order to exceed the precision that factory ammo could provide, if it used the same bullet I am using, I would had to work at it, because factory ammo is good and match factory ammo is very good. I exceed the performance of any factory ammo, for my purposes because I use at bullet that exceeds the specs of any bullet currently factory loaded and also because I fine tuned it to my rifle.
If I were to step back and start loading 175gr SMKs, I would have to work very hard to produce ammo with those bullets that would be more precise than factory match ammo with that exact same bullet.
When you were hesitating about the bullet, and wanted to wait to see how either one would perform in your rifle before committing to a bullet, I was just pointing out that I chose the bullet first, the twist and chambering second and the load third. I did not hesitate on selecting the bullet: I bought several thousands and then developed a load in my rifle for it. I just don't believe that certain barrels would hate a specific bullet provided the twist was adequate.
I made sure the twist in my barrels was more than adequate and then developed the load and went to competitions.
I rank the canard "every barrel is a law unto themselves," or "your barrel will tell you what it likes" right up there with "buy once, cry once" as brain-dead statements.
Choose the bullet that you want to use; get the proper twist, provide your gunsmith with a dummy round loaded the way you want it and then go develop your load in 50 rounds or less.
I just read fritz's post, and as usual, he gets it dead on.
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