338 lapua AI or 338 lapua imp

Glock-a-maniac said:
I'm running a 40degree shouldered 338LM and it feeds just fine. I think with the sharper shoulder then the standard it definitely helps brass life by the sheer lack of brass growth. As far as the improving the case or not, if you're a hand loader, 111.5gr of powder vs around 100gr is substantial. My bullets are supersonic out to 2700yds.
Mutt, it largely depends on how much you want to spend on a new reamer if your local gunsmith doesn't have it. If he has something that is very close and it works, go with it. I've come to realize that in the reamer world, some guys give their reamers a name after changing dimensions ever so slightly hoping that someone will imagine up a difference and make them famous.

THat's my thought.
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:slap:
 
Where some of you are comming up with 2,700 yds. is beyond me
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Didn't question him on shooting that range. Was trying to figure out where he came up with the numbers or what bullet he was using. Someone piss in your cornflakes or somethin? See above post by Max Owner. Should clear things up for ya chief.
 
2bad4u2 said:
I didn't hear him make the claim he's doing anything at that range. Most individuals shooting .338 LM are suggesting around 1,600-1,800 yds. as maximum effective range for the cartridge.

Where some of you are comming up with 2,700 yds. is beyond me. What difference does it make if it's supersonic if it isn't accurate?
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Good point. I think at 2700yds, you'd be lucky to see a
4x8 sheet of plywood. I guess it all depends what your definition of accuracy is. That boils down to the maker of the gun. Ask Bradtothebone how he likes his custom Lapua AI that came with load developement that he tested with a three shot group of .557 at 300m. I know that doesn't tell you what it's doing at a mile but it's a damn good start.

I just got back from the range and the group that showed the best promise was three shots
.460 @ 100yds with 112gr of US869. I cronod the bullets at 3100fps. I'd like to load 112.5 and 113gr as well to be sure I've found the right harmonics but this will do for now.
The summerland shoot will be interesting because of the number of big boomers out there as well as some level 2 armour also showing up so we'll have more results after that regarding penetration at long distances.
Last year at the mile marker, I was consistently hitting a dog sized rock and the bullet was traveling at 1429fps with energy of 1359ft/lbs. I wouldn't want to be a dog at that distance.
I'm not sure at what velocity or ft/lbs of energy a bullet becomes a misquito bite but if any of you have info on this I'd be interested to know.
 
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Let's say that the 300gr MK has been used to effectively take game at VEEEERRRRRYYYYYY Long distances.

There is little issue with the MK tumbling beyond 2300yds. A few have had very good success at further distances. 10 twist and you are good.

Glock, test you load as far as you can. Tune not just for accuracy but also vertical stringing.

A 1/2" group at 100yds can easily turn into an 11" group at 500yds if things are out of whack. Been there, done that.

I test min 200yds then confirm at 300m. From there, its just dial and lean.

PM me to discuss the Summerland Shoot.

Jerry
 
That makes a lot of sense Mystic. That is exactly what happened to me when I did load developement with 250gr Lapua Scenars. I had a great load at 100 and 200 but at 600yds, I was throwing a huge group (larger then 18") This gun loves the 300gr SMK however. It's the same bullet as I was using last year at Summerland.
 
Of course, there is really no such thing as the 338 Lapua AI. Ackley was dead before the 338 Lapua was introduced so it is unlikely he ever did anything with it. Of course, one may call any cartridge whatever he wants I suppose.
Bullets can be subsonic and still be accurate. It is only at the transition from super to subsonic that accuracy deteriorates. Regards, Bill
 
I think P.O. Ackley deserves his name on modern calibers purely out of respect for what his contributions to ballistics. And improving with Ackleys theory applied sums up what has been done to the cartridge. I could call it 'Enhanced' or 'Extreme' or even vainly name it after the gunmaker who appiled the Ackley threory to a modern caliber, but in the end the Ackley factor has been applied to this chamber.
 
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Leeper said:
Bullets can be subsonic and still be accurate. It is only at the transition from super to subsonic that accuracy deteriorates. Regards, Bill
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Bill, been pondering this 'factoid' for years now. Like you, I have seen bullets that didn't make the transistion 'gracefully'. However, bullets that do are as accurate all the way along ie 1/2 min while supersonic, maintains 1/2 min when subsonic. Just conditions have a more dramatic affect due to increased time of flight.

I confirmed this last fall when I was shooting 75gr Amax out of my 223 at 1000m. Based on ballistic charts, this bullet is right on the transonic range. Shouldn't do well. However, accuracy never changed at 1000yds vs 1100yds. Was sub MOA consistently.

Second point would be from Mr. Newton. Bullets don't steer and if bumped/wobbled by the compressive force of the air, they are going to continue on their disturbed path and fall out of the sky/loose accuracy.

I feel that if a bullet will make the transition, accuracy will be retained through its entire flight path.

Jerry
 
Mystic, I believe that to be true as well. As for Our 338LM AI, if I came up with it, I'd call it Troy's Kick ASS combo, but I didn't so I'm leaving the writing on my barrel the same as the writing on the reamer.
 
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