Reloading for the .338 Lapua Mag.

P

pearidge

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Basically, what I was wanting to know is if it is safe to have the bullet jammed into the lands or not. I know its a high pressure round, and would rather not have one blow beside my head. Do any of you competitors or shooters load this way. Or do you some of you just touch the lands, or do you back of say .010.
I'll be using Lapua brass, and the action is a Stiller Predator XL.

Thanks.
 
I started last Sat. on my barrel break-in procedure with a new .338 Lap. Imp.. I only got 5 rounds down the barrel before I ran out of time, it takes quite a bit to clean between the first few rounds of break-in and I ran out of light. Anyway, I'll share with you my procedure. I break in with 1 Lapua case completely prepping and annealing after each round. I record velocity then shoulder and case length after each shot. Each shot is increased with 1.5 G of powder and all the bullets are seated to touch the lands, 3.110 in this particular chamber. I started with 90 G of R25 and finished the day with 95.5 producing a velocity of 2966 fps. Naturally the cleaning between shots takes allot of time, 36" krieger a big case, bullet and a bit of powder. The action is a 10" bat and the barrel is blocked. Their are some pics of it in the GD forum under "How To" if your interested.
Once the barrel cleans easily I'll start the load development procedure. I keep the bullet on the lands until I find a satisfactory charge, then, if I have to tweak the group or tighten the ES I'll start backing the bullet off in increments of .005 of an ". I do the load development at 300 yards.
Good luck
vinny
 
Thanks vinny. The barrel is already broken in. It cleans like a dream. So far, I have only shot factory Lapua and Black Hills ammo. I recently got everything I needed to start reloading for it. Took forever to get my dies, but thats ok. I'll start by just barely touching the lands, and will back off accordingly.

I'm still open to ideas though.
 
Ask away! Plenty of people here willing to help! I'm going back to VT tomorrow after school to work on it, I'll let you know what transpires.
vinny
 
pearidge,
I fired a 338 Yogi for several years in BR competition. There isn't anything you can't do to this round that you can do to other rounds. Meaning... jamming the bullets is fine. Remember chamber pressure is chamber pressure. 60K PSI is 60K PSI regardless of whether the case is a 338 or a 6PPC. It's really the total square inches of these bigger rounds that adds up to more bolt thrust. Jerry builds good equipment and this is why he offers this bolt face in the XL version and not a smaller action. It's not whether the case will fit in or come out of the ejection port. It really is about safety and keeping enough shear strenght behind the chamber. This is why action makers and gunbuilders only recommend the bigger actions for the .580" bolt face rounds.

another words... just use standard safety practices while loading and adjust accordinglly to the pressure signs.

But I will mention this.... mine was done on a 2x10 BAT action and the bigger tenon diameter and longer bolt handle sometimes will hide pressure signs better than smaller actions. Meaning bolt lift is easier because of mechanical leverage and the larger tenon diameter of the BAT action doesn't allow as much stretch during peak chamber pressure. So you get the feeling of not running as much pressure when it's starting to get up there. Pay attention to your loads and case life. Case life will really tell you how close you are running on pressure. If you use Lapua brass and only get 3-5 fires and the primer pockets are really loose (but the pressure "feels" and measures fine) your getting up there.
So just pay attention and you will be fine. And when in doubt ask questions. There are plenty here to help as Vinny already stated. Including some good well know gunsmiths and action makers that have built these big guns.

Steve
 
vinny said:
and all the bullets are seated to touch the lands, 3.110 in this particular chamber. Good luck
vinny
Click to expand...

3.110........Why so short??? If I remember right, the couple that I did were 3.725 (mag restricted) in an AR 30, and 3.755 in a custom built on a MK V action.
 
Tod Soeby said:
3.110........Why so short??? If I remember right, the couple that I did were 3.725 (mag restricted) in an AR 30, and 3.755 in a custom built on a MK V action.
Click to expand...

I don't know?

I measure from Base of case to ogive using a Davidson base and matching ogive comparator, 3.110 just touching the lands. I'm not measuring from the tip of the bullet but from the ogive which might be the difference.
vinny
 
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vinny said:
I don't know?

I measure from Base of case to ogive using a Davidson base and matching ogive comparator, 3.110 just touching the lands. I'm not measuring from the tip of the bullet but from the ogive which might be the difference.
vinny
Click to expand...

Yep...that would explain it. Just out of curiosity....what is your oal??
 
Tod Soeby said:
Yep...that would explain it. Just out of curiosity....what is your oal??
Click to expand...

I'll get back to ya on this. Everything is in VT and I'm in NY, heading back tonight to continue working on it tomorrow.
vinny
 
Vinny,
are you shooting the 300 SMK at 2966? Are your shoulders a standard 40 deg. with the improved? Do you think you will get 3000 by the time you are done?
 
shootn1000 said:
Vinny,
are you shooting the 300 SMK at 2966? Are your shoulders a standard 40 deg. with the improved? Do you think you will get 3000 by the time you are done?
Click to expand...




yes, 300 smk. no, 35 deg. shoulder . 96G of R25 gave me 2966 FPS. Bullet seated touching the land.


I am still working on breaking in the barrel, so I don't know what FPS will be yet. Obvious it depends on what groups best at 300 yards. I will be happy to let you know what happens when I get back from Vermont.
vinny
 
I look forward to hearing your results. I am getting ready to build this gun myself, and was just curious about REAL results, not sombody bragging on their equipment. Best of luck, and i will keep an eye out on the post. TC
 
Keep us posted; I'll be starting to do my own load development for this chambering in a few weeks when my rifle shows up.

JeffVN
 
I'm sorry it took sooooo much time to get some "REAL results" to ya. This is what the gun likes.

Two nodes, one at 93 grains of R25 2910 fps and the upper at 95 grains at 3005 fps. Both shot multiple 3 shot 3/4" groups at 300 yards with single digit es. Last weekend I shot at 1000 yards over the chrony seating depth variations, starting hard in the lands then backing off in increments of .020. It went like this, 3.170, 3.150, 3.130, 3.110, 3.090. I first shot 1 of each seating depth identified as F2-6 working up from 3.090 to 3.170. There is no vertical string in the shot placement between 3.090 and 3.110 having 3+" of horizontal. 3.130 was all on its own then 3.150 and 3.170 had no vertical with 3-" of horizontal. I then followed up with 3 shot groups identified as A1,2,3, B1,2,3, C1,2,3, D1,2,3, E1,2,3 of same seating depths as F2-6 and when taking into consideration the difference in average velocity between the groups and how they appeared on paper at 1K I'm narrowing the seating depth down to the following for this weeks testing: 3.100, 3.120 and, 3.160. Obviously I'm meeting the most promising of seating depth's in the middle:3.100, between 3.090 and 3.110: 3.120, between 3.110 and 3.130 and 3.160 between 3.150 and 3.170. I should add that I'm attributing the horizontal stringing of groups B,C and, E to conditions. I waited between shots to try and keep the barrel from heating up and it was a little breezy.

I'll post for ya how it goes. Hope its helps.
vinny

I attached a photo of the first round of seating depth tests. I'll give a quick explanation:
The "Fs" are the single shots I spoke of and the A-E are the 3 shot groups.
F1 is a fouler
F2 is group "A" at 3.090 average velocity 2952
F3 is group "B" at 3.110 average velocity 2948
F4 is group "C" at 3.130 average velocity 2954
F5 is group "D" at 3.150 average velocity 2983
F6 is group "E" at 3.170 average velocity 2999
 

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Any more updates ?

I looked for the photos and could not find them, mind posting them here ?
 
Marine sniper said:
I am asking you.
Click to expand...


I don't mind at all. I'll try to post the same pic. here of the 1k target I used to see how the different seating depths looked on paper.

I'll have more info hopefully Sat. night after LG and I'll post it when I get back Sunday
 

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vinny said:
I don't mind at all. I'll try to post the same pic. here of the 1k target I used to see how the different seating depths looked on paper.

I'll have more info hopefully Sat. night after LG and I'll post it when I get back Sunday
Click to expand...

I am interested in building a big 338. I like how detailed you are and how well the rifle shoots. Thanks for the help.

A pic of the rifle would be cool.

John
 
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