New 112 Target 338 LM with Extremely Short Throat

[Harpoon1]

I’ve put 120 rounds thru the gun since getting it last week, with mostly 300 grn Nosler CC’s. Shot great, have been very pleased so far with the accuracy and the gun in general.

Then I finally got around to measuring the throat and base to ogive today and it’s looks like, when I load to the recommended COL for that bullet, and what I’ve been using, I’ve got a minimum of .065” of jam. Minimum! About fell out of my chair.

Haven’t really seen any overly excessive signs of pressure other than some slight firing pin cratering, and I mean very slight and only at the very upper end of the charges. And I did finally pierce 1 primer with a slightly over max load, after seeing no real signs of pressure with the same charge right before it.

So far, I’ve been using enough neck tension that I can still extract the round without pulling the bullet. And, enough tension that the bullet is not being driven back into the case compressing the load, at least internally.

So, what to do? I was going to back off anyway and shoot one the lower nodes most of the time, and take it easy on the components and me. Just wondering if I’m literally playing Russian roulette, shooting it with that much jam?

Keep shooting it or send it back?

[celltech]

Are you sure you are jamming it 65 thou? If you chamber one and pull it back out, has the bullet been marred? Jamming it is not dangerous in and of itself...just depends on the charge you have behind it. If the gun is accurate and you enjoy it, then load for the gun and don't pay attention to the recommended coal.

[Harpoon1]

Yep, it’s marred and I’m positive, unfortunately, it’s a minimum of “65 thou”. Measured it again and again and again with the Hornady/Stoney Creek tool. Then made up a dummy round with magic marker on the ogive, tried multiples lengths to verify............it’s crazy short.

Just went thru the same thing but worse with a 6.5 Grendel barrel, from Alexander Arms no less. It was cut so short the round wouldn’t even chamber. How does that make it out the door? Wouldn’t even chamber, amazing. Then they act like I must be mistaken. Unreal.

[CFJunkie]

With a chamber that short, factory ammo should also be jammed in the rifling.
I would suggest loading a factory round with a blackened bullet, close the bolt, extract the round with the marks on the bullet, and take pictures of the marks.
Measure the O.A.L of the round and base to ogive and photograph the measurement including the caliper readings for both.
Report it to Savage on their web site and include the pictures.
Savage shouldn't argue with factory ammo jammed in the rifling especially since factory ammo is normally seated back about 0.005 from SAAMI recommendations to avoid such problems.
I can understand a company's hesitation about complaints with hand loads without adequate documentation because there are a lot of people who are measurement challenged.
(I'm not saying you are but you probably know some who are.)

I had a 12 LRP in 6.5mm that had a tight chamber, not short but tight, that caused increased pressure symptoms even with light loads.
I documented the problem, took pictures of the primers for loads at 57,000 psi, 47,000 psi and 37,000 psi that all showed flattened primers, even the loads shot at a minimum load for the caliber.
They immediately sent me a UPS return label, bored out the chamber a few thousands and the problem went away. Didn't cost me anything and the rifle shoots even more accurately than it did before, probably because the shooter isn't obsessing about over pressure.

[Harpoon1]

Good ideas if I decide to pursue that route.

As I mentioned earlier I intend to use a lower node, well below the max charge. So Im wondering whether I should reduce the jam by shoving the bullet deeper in the case, leaving it jammed 015-.020. That’s about as far as I can go seating it deeper before running out of the bearing surface and the case neck. Or, just leave it jammed .065 for now and press on?

Anybody care to hazard a guess which way would accelerate the throat erosion more quickly, jammed a little or jammed a lot?

[sharpshooter]

Throat erosion is not caused by bullets... it's caused by heat.

[CFJunkie]

Harpoon1,

Seating a bullet deeper into the brass actually increases the pressure in the case and seating it out into the chamber reduces the pressure by about the same amount until the bullet ogive makes contact with the rifling. Ehen the bullet is jammed in the rifling, there is a spike in pressure because the bullet doesn't move before the pressure rises enough to press it into the rifling.

If you are reducing the load considerably, you should be OK moving the bullet back into the brass because moving the bullet back into the brass.
For example. of you seated the bullet deeper into the brass by 0.050, it would increase the pressure by about 600 psi which would be equivalent to increasing the powder load by 0.5 grains or so.
I can't give you exact amounts because I don't know the powder or bullet you are using, but that is a pretty good approximation.
But if you also drop the charge by 1 grain, you actually should be reducing net pressure.

[Harpoon1]

Harpoon1,

Seating a bullet deeper into the brass actually increases the pressure in the case and seating it out into the chamber reduces the pressure by about the same amount until the bullet ogive makes contact with the rifling. Ehen the bullet is jammed in the rifling, there is a spike in pressure because the bullet doesn't move before the pressure rises enough to press it into the rifling.

If you are reducing the load considerably, you should be OK moving the bullet back into the brass because moving the bullet back into the brass.
For example. of you seated the bullet deeper into the brass by 0.050, it would increase the pressure by about 600 psi which would be equivalent to increasing the powder load by 0.5 grains or so.
I can't give you exact amounts because I don't know the powder or bullet you are using, but that is a pretty good approximation.
But if you also drop the charge by 1 grain, you actually should be reducing net pressure.


Yep, got that. What I don’t know is, whether there is any difference in presssure with rounds being
jammed to different degrees, “a little” or “a lot”?

I really can’t get it any shorter than being jammed .015”. Well, I guess I could but, that’s where the bearing surface is starting to get shoved back past the case mouth.

So, if they’re going to be jammed regardless, does it really matter whether it’s .015 or .065?

[Harpoon1]

Throat erosion is not caused by bullets... it's caused by heat.

Yes, I know. :cool:

The thought was, the bullet being jammed deeper “might” offer more initial resistance, causing higher pressure (and heat) than the bullet barely being jammed.

[celltech]

What does it matter if you either load it past the bearing surface or force it down when chambering the round? If it's that bad I have changed my mind and say send it back. Just what bullet are you loading???

[Harpoon1]

What does it matter if you either load it past the bearing surface or force it down when chambering the round? If it's that bad I have changed my mind and say send it back. Just what bullet are you loading???

Like I said in the OP, I’m using enough neck tension that it’s not being forced back down into the case when chambering the round.

Nosler 300 CC’s

[Zargon123]

You could always consider renting a Uni Throater to increase you free bore.

[yobuck]

Id be taking it to a "good" smith and have him work on it.
You got what you got from Savage, and no assurance you wont get more of the same.
When it gets fixed id also be trying 250 gr bullets in lieu of the 300s.
That case dosent generate enough horse power to get the max results from the 300 gr bullets.

[Zargon123]

That case dosent generate enough horse power to get the max results from the 300 gr bullets.

What? A .338 Laupa doesn't have enough horse power for a 300gr bullet? Couldn't disagree more and I've owned 3 or 4(Sav, Rem and a Barnard custom).

Give the Berger 300gr Hybrid OTM Tactical a try.

[Zargon123]

Prefer Berger, but often achieve similar results with SMK's.

[efm77]

Savages are known for having tight chambers. What COAL are you going by? The reason I ask that is because when I loaded mine to the COAL listed from Alliant (was using RL33 load data), it wouldn't chamber without hitting the lands. But when I used the COAL listed in Hornady's manual, it chambered fine. But if you seat the bullet deeper you will have to reduce your powder charge accordingly. I too have a 112 Magnum Target and other than that, haven't had any problems, and it shoots really well. I've got a 30" barrel I'm eventually going to put on it, but for now still using the factory barrel and just loading to a length to accommodate the chamber as is.

[yobuck]

What? A .338 Laupa doesn't have enough horse power for a 300gr bullet? Couldn't disagree more and I've owned 3 or 4(Sav, Rem and a Barnard custom).

Give the Berger 300gr Hybrid OTM Tactical a try.
Try any of them you like, not saying you wont get an accurate load, simply saying a 250 will out perform it to probably about 1500 yds because of higher velocity. Some guys I know are even using them in 338x378s which turns up more velocity than the standard Lapua.
Use what ever you like, but your only kidding yourself in thinking the 300 gr is a superior bullet simply due to a higher BC number on the box. If so, why then dosent everybody use 240s in a 300 Win Mag if a higher BC bullet would make it better?
That would be because you cant drive them fast enough to get the BC benefit of that bullet with that cartridge, and the same is true with 338s.

[Zargon123]

Over 300 yards BC matters. Higher BC means more retained velocity, less drop and significantly less wind drift. Heavier bullets also retain more energy down range. When you shoot long distance(<500 yards) you learn the benefits of a heavier bullet.

Pretty simply actually. If bullet weight didn't matter we'd all be shooting 4,000 fps 40gr .204 Rugers. Which I have and although outstanding out to 300+ yards they're pretty useless over 400 yards.

[Harpoon1]

You could always consider renting a Uni Throater to increase you free bore.

Im working on this now. If I send it back to Savage and they clean/open it up, I still get, what I get, back from Savage. Buying/renting a reamer or “throater” I can get exactly what I want. It’s a no brainer.

[Harpoon1]

..........Give the Berger 300gr Hybrid OTM Tactical a try.


Yeah Ive considered that and will probably try some, but the Hornady 230 ELD-X I tried we’re still jammed also. I know the ogive is different than the Bergers but the ELD 230 are pretty small, comparatively.

And the Noslers are about 1/2 what the Bergers cost. Be cheaper in the long run to just buy a new barrel and keep shooting the Noslers! :cool: