OK, I have a 6.5x55, 25-06,7x57, 30-06, 300WSM, and a 300 win mag. I am really thinking about building a .243 Ackley on a Mauser that I just aquired. Probably getting a 24in Shilen bbl and an ambi-thumbhole from MPI. Is this cartridge a good choice for shots out to 500yds? I am all ears, let me know your thoughts. Checking back later. Thanks!

The cartridge certainly has "the right stuff" and available bullet selection if you build a capable rifle around it.

It would be a lot better in an action other than a Mauser. The long lock time is a hinderance. A regular .243 Winchester would be just as good.

Please Tell Me What Lock Time, Has To Do with Case Capacity..

I do know a Mauser is about the last action I'd build it on, that for sure. But if you can saddle with a turd of thumbhole stock you might as well go all in.

Tell me about YOUR 243AI?

Well,c'mon guys someone talk about the cartridge......cause I have a 6mm 8 twist SS Bartlein here that I haven't decided what to do with......

Same boat here.

Ditto!!

It might be ok for a DG rifle. Wouldn't even think about an AI. This is the 21st century, and they sucked even back in the day.

Hell ya...easily. 105 VLD's, or 107 Sierra's combined with a 8 twist makes a nice Long range .243 or .243AI.

Wanna sell your Bartlein?

Good grief!......

I realize that a Mauser isn't as desireable as some higher dollar action, but that being said, I have built several sub-moa Mausers in the past. Amazing things, those lathes! Don't start the whole MPI thing again. Nuff said.

Swampman, I am making a Ti firing pin and going to try some different springs to take care of lock time. Good point though.

More on the cartridge, I have no experience with the 243 AI. Has anyone busted whitetail sized game 400-500 with it?

Seriously Bob, what are you wanting to know about?

This 243AI has went through a couple different stock set-ups but the barreled action is still same/same.

When I first got it back a couple years ago the first bullets I ran were the vld's. This was before R-17 and I was running R-22 at that time. I hit an accuracy node right around 3050fps(iirc). That load shot great in my rilfe and I worked up to 3150 with '22 but never could get to that next accurate node so I stuck wit the 3050 load. This is from when I tried them the first time.



Now when I originally got that rifle it showed up on the 12th of November (2008), I worked up some 100yd loads on the 13th, on the 14th SuperSeal110 and I went and shot some long range groups and on the 15th (opening day of rifle season here) I shot a buck with it.

This is the first group out of the rifle at 700.



Here's SuperSeal110 with the first 5 shots out of the rifle at 1000yds. The group was low and right but we were just working with rough drops from JBM. That's why we put them on the large target just to see how it would shoot. And that was with just a 1" Leupold 3.5-10x in Talley Light-Weights.



The buck I shot was pretty much an absolute worst case scenario for the VLD. He wasn't a big buck, just an average buck for the area we were hunting in. I was walking an old logging road in the afternoon heading back to a ridge that overlooks a good clearcut and I spotted him down in the cedars at prolly around 60-70yds. He was quartering toward me and getting closer. I usually carry a rifle with rounds in the mag, but on an empty chamber. I just chambered a round and shot him in the front part of the shoulder and the bullet went in about 3" through the shoulder and then came apart in the chest cavity. It was absolutely devastating and I just knew that when I walked down to him the shoulder was going to be a mess. It wasn't. ALL the damage was inside the chest cavity. If you do some reading you'll find that just about everyone who uses the VLD says the exact same thing, "they go in a few inches before they every start to open up, and then they open up violently". Now I'm going to give them a pretty good run this year and see how I like them.



Here's the specs.

Trued Rem700 S/A that this is its 3rd barrel.
Rock Creek Fluted SS Rem Varmint Countour 1-9"twist at 24"
Throated to put 105Amaxs in the lands in a factory Rem mag-box

The way it's pictured above is how it was originally set up with a MannersT2 and HS DBM bottom metal. So I ran that T2 for quite awhile before I traded it off. Then I dropped the barreled action into an A5 and still used the HS DBM bottom metal and shot it like that up until about two months ago. Here's what it looked like in the A5. This 5-shot group was one shot with it at 1000yds. I had also swapped glass at some point around this time. I pulled the 1" leupold in favor of a Leupold Mark4 30mm 3.5-10x40 w/M1's and put on a set of Seekins' 30mm al rings and one of his 20mao rails.



About 2 months ago SuperSeal110 was selling an A5 with Rem Varmint contour inlet and ADL bottom metal that he had ordered for his 243AI build and I snatched that one up since I really wanted to switch this rig to ADL.

So this is what it looks like now in the ADL A5 and I'm still running the same 3.5-10x40 Mark4 as well.

Shot this one a couple weeks ago at 705yds.



I've just about 1000rounds through it now. I don't really know where I'll end at with barrel life but am hoping to get 2000-2500 out of it....we'll see. When this barrel is gone I'm going to re-barrel again to 243AI. It'll be another Rem Varmint contour but I'm going to skip the flutes and have it cut to 23". It should balance about the same and I'm not worried about any kind of speed difference 1" of barrel will make. Mostly the change is just because of the cost of fluting. I don't feel it's worth it to put the money for fluting in the next barrel is all.

I thought i shot all my 6mm 105VLD's up but was looking through my bullets the other day and found a few left. I loaded some up to feed from the mag and they were jumping .040". I run 44.5gr of '17 with moly'd 105Amax's and these VLD's I had previously moly'd, so i just backed off to 44 gr and shot them on paper and they went into 1/2"(ish) at 100. I'm gonna load up the last 20 or i have on hand and shoot them at distance and see how that load holds up. If it holds up then I'm done with load work up. The 44.5gr 105Amax load is chrono'd at 3250 so I'm thinking I'm at around +-3200 with the 44gr load.

POI was just a hair left of where it shoots the Amax's.

[img]http://i49.photobucket.com/albums/f281/brdeano/Shooting/IMG_20110316_172815.jpg[/img]

Excellent post, Brad. Your .243ai sure shoots good. I'm hoping mine shoots the same.

Awesome rig! I guess that answers my question about the .243AI and distance. Can't wait to get started on my project.

Brad: Thanks, that's what I wated to know about because I'll likely use a Rem 700 action....and I'm interested in a 6mm for use with the heavier Bergers and the Amax bullets....this will be for woodchucks and varmints, here and out west.Maybe deer and antelope as well.

I assume yours is a short Rem 700?

And how do you form the AI case?

Do you feel the velocity advantage is enough more than,say, a 6XC to be worthwhile,comsidering the bullets I'll be using?

Nice buck BTW.....

Works pretty well at killing stuff out to at least 600. I do not think I have taken any animals other than crows past 600 but both of the pictured above were between 500 and 600.

500 yds is nothing for that or the standard .243 round, heck I do that with my .223...course thats just on p-dogs.
A pal is having a benchmark bbl made for his Ruger action. He wants a harder hitting round than his .220 swift and he shoots that to 600+ all the time.
I just dont think a 1/12 twist is going to be what he thinks it will be after its done & said.
Im going to have a .243AI bbl made for my Savage action when I get the current build done myself.

Bob, mine's on a S/A 700, all the specs are listed in that long post (grin)

I just FF with max(ish) loads of the parent chambering. I really don't know about the 6XC so I can't say. How fast are they getting the 105's up to in it? I'm running them at 3250 via '17 and moly. Some guys don't like the FF thing and bitch about wasting barrel life, but I'm still working on the same inital 100 pc's of Lapua brass I started with (minus a few I've lost here and there). I just don't buy into the wasting barrel life argument. This batch of brass could very likely last as long as the barrel. I've not yet had to trim the brass yet either, I don't clean primer pockets, barely ever tumble them.......I just like to load 'em and shoot 'em. (grin)

The 6mm-284 would be better IMO. That pile driver firing pin in that Mauser isn't going to help your accuracy but it will ignite a primer.

Guess you missed this the first time around.



So now maybe you could tell me about your 6-284 while your at it. Good luck.

The wildcats are dead and have been for years. They offer nothing. That said if you want to waste your money make it worth your while. The AIs are no better that their factory parents.

It's official...you're an idiot.

I'll give you one thing.....you are funny.

So tell me about your 243AI and 6-284.

Northeastern Oklahoma had a lot of quarter-mile section fences, especially around Chelsea. Whitetails died quickly at a quarter mile with 85 grain Sierra HPBT bullets started out at 3000 fps muzzle velocity. There is a lot of open pasture land there. The shots were taken from one fence across the open pasture to deer walking down the other fence line. As a kid, I watched my shooting mentor do this several times over the years. He normally used the heart shot with his 6mm Remington in a M700 BDL Varmint Special.

A large number of coyotes met their demise at the same distance from the same load. Crows sitting in some of the Osage Orange trees along the fence also met the same fate. That particular fence line was the game highway.

At 600 yards, the same bullet would just pencil through a coyote. My friend felt that 600 yards was about the limit for clean kills on coyotes and did not shoot deer at that range.

The same load also killed hogs in Southeastern Oklahoma on timber land at much shorter ranges.

My shooting mentor was an exceptional rifleman.

Many years later, I took large Western Kansas whitetails/mule deer with my 6mm using the same bullet at the same speed around Plainville. There is a lot of open space there. You can get close shots in a gully or creek bottom. You can also get long shots across a stubble field. And in that part of Kansas, wind is almost always a factor. I made a kill one year at over 400 paces across a wheat stubble field. That was a big doe, much bigger than those in Oklahoma. Those big round hay bales make good shooting rests.

If a 6mm Remington reliably kills deer at 440 yards, I suspect that the standard .243 Winchester would, too. I am not sure how much further the improved version will extend the range. Other factors such as wind, mirage, and shooter ability get real important much past 300 yards. These days I have a self-imposed limit of 250 yards. Years ago I burned up a lot of ammo in practice and varmint shooting. These days I am lucky to get to the range a few times per year.

In open country, I would feel confident with that setup on deer were I still up to the task. However, I lived in South Carolina for a few years and did some shooting across soybean fields from tree stands. There I would not use the .243 on deer at that kind of range. The reason is that sometimes the deer will run a ways even with a heart-lung shot. The bean fields I hunted over were surrounded by thick woods. The bullet did not always exit and sometimes there was not much of a blood trail. In Oklahoma and Kansas we could see literally for miles and could follow a deer with our eyes for 40 to 50 yards if one ran. In South Carolina, I lost a doe that ran from the field into the woods. We found it the next day with a dog, but the meat was lost. The hit was good but no blood trail. After that I switched to a heavier caliber.

So, in my experience, the 6mm will kill reliably out to a quarter mile. Also in my experience, the deer will sometimes run a few yards. I would not use it, improved or not, at that distance in wooded country.

That extra 50fps the AI gives you will make a huge difference;)

Of course is you exceed safe pressure levels you can gain a few more fps.

He is the gift that keeps on giving...

If I were inclined to build a 243, the AI would easily get the nod. It wont' cost a dime more, save for the dies, and why not take the advantage and attempt to keep the turbulence point in the neck on top of it.

Even if you are like Brad..... the node isn't at max, it'll still be humming right along. If Brad went 243, and had to back off to find the node, he'd be another 100 or so fps slower.

Just because its AI doesn't mean you HAVE to drive it that way but at least you have the option.

Less Trimming And A Little More Case Capacity. Win-Win.

I don't own a .243, or the AI version, just the 6mm Rem.

Here's a link though, to an excellent article on the .243 and the .243AI: http://www.6mmbr.com/243Win.html

Guy

My long post might have been a little confusing. I just got on a roll and might have drifted of course a little once I got typing.

I only played with 1 box of VLD's when I first got the rifle and I couldn't hit the next node with '22, but I DID get it with '17. I'm not running them at 3050 since I made the switch.

I'm at 3250 w/the moly'd 105Amax's and 44.5gr of '17. I've shot a handful of moly'd 105VLD's with 44gr of '17 and I haven't poked them through a chrony....yet. I'm "guessing" they're around the 3200 range as is, but I'm not going to work up any higher with the VLD until I sit down behind the chrony.

Come on, you can do better than that. Rather than talk out of your ass just post your experiences. There's always google.

I fear that he IS posting his experiences...which amount to........


talking out his ass...

So true.

I need to shoot my .243AI here someday......course you know its outdated and wont offer me much over the original...

Should I go ahead and throw my .223AIs out?

what? Now i have to build a 243AI???? i hate you guys!!!! grins

lets not get crazy now! grins

You gain no advantages when firing off of golf carts.

How about if you "improved" your golf cart...you know..made it go faster...?

Ingwe done bumped his head. (grin) I think the 223AI would probably the one I would part with.

Hmmm.....a Tactical golf cart!

Dat would be "Tacticool"...!!

Swampy " Before"....




Swampy " After".....

Drop one of these bad boys in there and maybe it would.

Tell me that's not.......really?

It IS....

too FF!!!!

back to the OP, i like the idea of a 243AI but have absolutely no experiance with it. I've been a 6 Rem fan for a long long time and just got my first 243 recently. I'm starting to warm up to it but it's taking me a while... i might send it out to be AI'ed as i think that'll make me warm up to it faster...

Paul, you running 105's in the 6mm? You've ran the 223AI enough to know what it does when you stretch it out. The 243AI get to 1K still doing 1700+, needing just 20MOA of ele, and drifts 6MOA in a 10mph crosswind from a 250yd zero....that's nothing to sneeze at.

I'm ready...

TFF!

only two bullets i've shot in the 243 so far have been 80gr Bergers and 85 HPBT game kings. Used the 85's for deer this year and it worked, but not how i like. I have one box of 105Amax's to try but i'm running factory tube and don't know if it'll stabilize? i'll have to give it a try and see if it's worth it to go AI on this one or just get a new tube with the proper twist...

also, the berger bullets are a PAIN to get to shoot for some reason. i've tried them in 243, 6mm, and 308. I'm about to say screw it and just give up on trying them.. only one that had acceptable accuracy was the 243 with the 80's and those are varmint bullets...

Brad/Eddy: Good thread!The cartridge really moves along!

I did not realize but it is faster than the XC,which I asked about because we have a lot of club members who shoot it in matches.Case forming looks easy.....and a 5 grain advantage over the parent case will get significant with heavy bullets in such a small bore.

Not much not to like....and Lapua brass too.I will see if my smith has a reamer.

Thanks all!

Swamp, How can you say that a lighter firing pin with a faster spring, giving you a faster lock time, won't help with accuracy? Are you going to tell me that blueprinting a Mauser won't help with accuracy as well? Your thoughts please.

I had great luck with the 105g Speer spitzers on deer and elk out of my Rem 700 BDL in 243 in the early 70's before I switched to a 270 (mainly due to the grizzly population). Not sure how they would hold up at 240 Wby Mag velocities, but they did great at 3000 fps out of my 243.

It will help but an antique design can only be helped so much. The Mauser is fine where accuracy isn't the primary requirement. For me anyway a .243 should be very accurate. The reason the Remington 721 (later the Model 700) was invented is because Bench Rest shooters couldn't get great accuracy with the actions available at that time. Nothing has changed.

The Hornady A-Max will out shoot the Bergers.

Nothing against the 700. I own four of them and they are all sub-moa rifles. The only other Mauser I have built right now is my 7x57, and it too is sub-moa. Again, if the action and bolt are trued, with a quality bbl, the cartridge does not care one bit if it's a Mauser or Rem 700. Tight tolerences and a good machinist is what gives a rifle it's potential, not the name on the receiver. The guy squeezing the trigger gets some credit as well.

The 3 minute lock time of the Mauser, and the huge extractor pulling the cartridge to one side of the chamber helps too;)

A polished turd is still a turd.

You seem to be stuck on lock time. Read carefully, I am putting a Ti(titanium) firing pin with a speed spring. That decreases lock time. And, with neck sized AI brass, the chamber fit should be 1:1. Therefore, no effect caused by the extractor.

Does anyone shoot Accubonds in their 243 AI's I use them in my 25-06 and have great results.

Where are you seating them? Many bergers like to be jammed into the lands (not something I'd necessarily want to do for a hunting rifle).

If you have a remington .243, the factory twist should be fine for the 105 AMAXs, but possibly not enough for 105 Bergers.

My only experience with the Berger's has been w/105's in this 243AI. They shot good for me in the lands and it also looks like they just might work even now that I'm jumping them .040".

Brad, you said you were on your 3rd barrel on the 243AI. Out of curiosity, how many rounds are you getting before they puke?

Brand new to the .243 AI so take this FWIW. Just got my LH M700 SA back from the smith and finally got it to the range this weekend. Barrel is a 24� Remington factory take-off I bought from the classified here a couple of years ago.

After fireforming 50 cases this past Sunday, I checked the capacity increase from cases of the same lot. Notes are at home, but the average gain in case capacity (weighing cass water filled to the base of the neck) was about 2 grains of water, or a whopping 3.8% capacity increase.

Using the 1 in 4 rule, that should allow about a 1% increase in velocity. Figuring around 3000-3050 with 100 grain bullets for the parent, that gives us 3030 to 3080 fps. Obviously not something to write home via Priority Mail about.

Factory ammo, Remington 100 gr. Core-Lokts, gave just over 3000 fps in the original chamber, about 3020 IIRC, and rounds from the exact same box of ammo gave 2949 fps in the improved chamber, a velocity loss to be expected.

But in fireforming, my velocities were a bit puzzling. I was using max book loads (for the parent case) of RL-22 and H-4831 under Sierra and Hornady 100 grain bullets, 44 and 45 grains each. 45.0 grains of H4831 with a Hornady 100 BTSP in my 23.75� barrel gave 3135 fps, it gave 3096 fps with the sierra bullet. That�s cooking. In previous trials with this rifle I�ve gotten 3050 fps pretty easy with the same bullets and loads of 42.5 grains of IMR-4350 and (the exact load escapes me here) IMR-4831.

Now, this is a little fudgy logic, but the .243 loads have been tamed due to it�s propensity for wider pressure swings in any given string. So, I�m using loads that the books claim to give 3000 fps from their 24� test barrels, in a larger chamber, and getting 100+ fps more. Pressure signs (yeah, I know) were totally missing. Primers had a good, well rounded radius, bolt lift was easy, every subjective indication said pressure was very civilized.

Not that I�m unhappy, just cannot explain the increased velocities from this enlarged chamber. Well, maybe � I had the bullets seated to touch the lands for fireforming, that would be the only difference over the normal loads where bullets are about .020� off the lands. That alone would be telling evidence of being careful when you seat any bullet hard up against the lands. Oh well, something for more experimentation.

Anyway, my whole reason for AI�ing the .243 was not for increased velocity anyway. I just wanted to tame it�s internal ballistic weirdness and it�s humongous appetite for eating throats. Prior to AI�ing, this brand new barrel had just over 600 rounds through it of moderate loads, and throat erosion had already advanced .070�.

Now that I�m getting my target velocities with book loads for the parent I know pressures just have to be mild (a goal I increasingly strive for as I get older) and I�m not so worried about those famous kabooms with 100 grain bullets the .243 apparently likes to spring on people as the throat gets all eaten up, I�m a happy camper.

From jammed to .03 off. Someone mentioned in another thread that i should try even further. So, i'm going to give that a try and see what happens...

Sorry for the confusion. I just meant that this was an older Rem action that I've had 3 barrels on, not all 3 were 243AI's. First was a standard 22-250, then an 1-8"tw 22-250, now the 243AI barrel.

10-4....thanks for the clarification.

I'm sure you shoot the he11 out of your 243AI, but 3 barrels since '08 would be impressive.

If the 243AI was my only rilfe I'd be in trouble, 'cause that one is a bunch fun to shoot.

Lots of good info here! Just ordered my bbl from ER Shaw. 1/10 twist, figured for bullet weight between 85 and 100gr. .600 at the muzzle and 24in long. I have put together 2 remingtons with Shaw bbls and got great accuracy with them.

LUCK

Funny that the 260 gains a hair over 10% in capacity when AI'n verified pretty thoroughly here.
http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/4686301/all/260_Rem_or_AI

Not sure I understand, are you saying that the .260 Remington provides a source of humor that the .243 lacks?

I'm thinking something is off with either your math or your 243AI.
Per http://www.6mmbr.com/243win.html ,"The .243 AI delivers more velocity by virtue of enhanced case capacity--roughly five grains more H20 capacity than a standard .243 Winchester. The .243 AI has a water capacity of approximately 57 to 58 grains, compared to 52-53 grains for the standard .243 Winchester."

Could be. Here is my raw data if you'd like to check it. All cases were filled with an eye dropper right to the base of the neck as checked under a magnifying glass and strong light. The .243 cases were fired in the previous chamber and had been neck sized only, I inserted a fired large rifle primer in each to keep the water from coming out of the flash hole and to keep that from influencing the weight differences from the fired AI cases.

All cases are Winchester from the same bag, twice fired before forming and trimmed to a uniform length after the first firing.

Formulas here are filled weight - empty weight = weight of water, all weight in grains.

.243
Case 1: 218.3 - 165.3 = 53 grains of water
Case 2: 215.6 - 163.3 = 52.3
Case 3: 217.4 - 164.7 = 52.7

(53 + 52.3 + 52.7) / 3 = 52.66666, called it 52.67 grains average

.243 AI cases
Case 1: 219.4 - 164.7 = 54.7
Case 2: 220.0 - 165.4 = 54.6
Case 3: 220.3 - 165.3 = 55.0
(54.7 + 54.6 + 55.0) / 3 = 54.766666, call it 54.76 average water capacity

54.76 - 52.67 = 2.09 grains increase.

2.09 / 52.67 = 0.0396, or call it 3.96% increase. In my earlier calculation I had used 54.7 instead of 54.76 so that accounts for the extra .16%.

Still, round that up to 4% and apply the 1 to 4 rule, which say that a given percentage increase in case capacity will give you roughly 1/4 that much percentage increase in velocity.

Figure 3000 fps as a nominal velocity for the .243 with 100 grain bullets.

3000 fps * 1% = 30 fps increase.

In the article you cite his fired cases have about 2 to 3 more grains than my Winchester cases so he could certainly have gotten a 5% increase.

5% * 1/4 = 1.25%

3000 fps * 1.25% = 37.5 fps increase. I concede that the author of the article beats me by 7.5 fps.

As I'm sure you are aware fps as a comparison isn't necessarily the most meaningful as pressure isn't always apples to apples.
Both 308 case based AI's I gave as examples showed about a 5 grain increase in water capacity. Your body shoulder junction measure .460?
With the minimum increase in capacity of your 243AI it sounds like you have a 243AAI-Almost Ackley Improved.

Hmmm I get 4 grains difference and 125fps difference using vv560 and 115 dtacs. If those are once fired they are possibly not fully formed. Of course not all reamers are created equal.

Yeah, Steel. I want another three shot group like this!

To answer the dimensional quesetion, three fired cases at random measure .4628", .4621" and .4625" at the shoulder junction. Ha, that beat your quoted figure by an incredibly large (in Lillliputian standards) average .00267"!!!

But before we go any further I have to ask, what is your point? Are you really trying to insult me based on minute differences in my reported results that differ from what you read on the internet?

Really?

That's a valid point. The throat on this chamber is quite short, 100 grain bullets seated to touch the lands still extend quite a bit below the neck junction. This was the very first chamber cut by this Clymer reamer which would make one think it is on the maximum side of spec. I bought it specifically for this job and the probability of creating a few more .243 AI's in the future.

I'll save the before numbers and measure teh cases again on the second firing in the Ackley chamber to see if the average capacity increases.

Still not sure why I was getting almost 135 fps more (3135 fps) with book loads for the .243 and the Sierra 100 Spitzer, that being the 45 gr. of H4350. That same load gave 3096 fps with the 100 grain Hornady. The 100 grain bullets were seated right to touch the lands, that's the only difference I can see.

But getting away from all this ballistic gack and trying to show that 1% of anything is somehow meaningful, I think the .243 loads in manuals were a bit shy of what could be possible simply due to the wider pressure variations in a given string that the parent case shows. They had to keep the average pressure down to avoid the possibility of any one round exceeding the maximum peak pressure.

Since the Ackley shape tames this and makes it behave better (so I have read and shall hopefully prove for myself), I would feel very comfortable running 100 grainers in the 3100 fps range. Especially since this rifle has a 24" barrel - well, about 23.75" since it was set back. If one had good pressure testing equipment and could work up loads in an individual rifle to reliably know pressures that figure could probably be exceeded as well.

But again, velocity increase was not my objective in this project. The goals were to tame that propensity for ballistic variation, to keep the throat from eroding so quickly, and to get the added benefit of any AI case to reduce or eliminate trimming.

When I get my .250 Savage AI back from the smith (the barrel is "on the lathe" as of yesterday), then I shall be happy to report capacity increases measured in pints of water and perhaps a few thousand feet per second velocity increases over the parent case.

Not trying to insult you at all. Just questioning the 3.8% capacity increase.

Amazing how people can bicker so much over stuff that doesn't matter. The .243 is semi-improved already. Blown out to AI the shoulder gets a lot steeper and moves forward, which changes body taper, but shoulder diameter hardly changes at all. I've no idea what that does to internal volume. The only thing that matters is what it does to how it shoots. My first 243AI was a rechambered factory 700 varmint barrel. Comparing accuracy loads......as a 243AI it shot 70's at the same speed it shot 60's before as a std. 243......3800fps. That's a good enough improvement to make it worthwhile. I've had a few re-barrels since then. Accurate velocity from a 25 & 26" barrel with 70's is 3855 + or - depending on which bullet/primer, and which gun. That combo works fine on pds or rockchucks at 500yds.

Thanks Ackman. Looking forward to getting mine together.

Weren't necessarily about the tube make but about the twist. Going 1-10" twist makes as much sense as screwing together a 22/250 with a 1-14"


LUCK

More uninformed posting. This and the one about a 50fps increase. You must be trying to look the fool.

In a 700 with the extractor capturing the case head on one side and the spring loaded ejector plunger pushing on the other, how is the situation any different?

Steel,
This is a deer and yote rifle. For bullets up to 120gr and VLD under 100, this is the ideal twist rate. What is your reccomendation for twist rates for these bullet weights?

I'd not go slower than 1-9", but that's because I would always want the option of running the 105 vld/amax in any rile I had put together. My lightweight 243AI (7#'s all up) is going to be running 105's as well. I've never had any issues running ligher bullets in fast twisted rifles, the fastest/lightest I've ran is the 40Vmax's in my 1-8" 22-250 and they shot great.

I just enjoy shooting longrange with all my rifles, and that's why the faster twist rates... at least for me.

Be sure and post up some results when you get it back.

I will, and thanks for all the info. I am kinda on a budget, truth be told, and got a really good deal on a new 1/10. I think it will work for what I am trying to get(I hope)

The short answer is it's not a bit different, though it would require that he understood the definition of headspace and how neither extractor has an effect on the final outcome of accuracy.

I too, regrettably considering the company; would not use a Mauser for the project, but that is due to the material that needs to be removed from the critical surfaces during a full blueprint that would render the case hardening useless and in need of another shot through the furnace.

The 243AI is a neat round for sure and I've grown quite fond of mine sitting in a McMillan Classic Compact.

Matt, it's good to see you back here!