Long throat?

[NWPA0311]

New to reloading and precision shooting so bear with me. I picked up a semi custom on trade a while back and never got to playing with it until recently. The previous owner didn't know too much about the gun other than, rem 700 SA 300wsm, manners stock with LRI spun on aftermarket barrel, jewel trigger and alpha mag. I contacted LRI and they had a record of the gun however did not have much info on it. The gun looks great however I have yet to shoot it.

I decided I wanted to try to the 200 grain ELDX bullets. Hornady recommends a coal of 2.885 to start. I figured I would see what it would be to the lands and using a dummy round I got a COAL of 3.0640. Does that mean this rifle has a long throat? That is essentially a .18 difference from the 2.885 hornady recommends. It does have an alpha mag which gives me the ability to load in the 2,97 range however that still seems like a huge jump. Could anyone shed some light on how the barrel was reamed and what my options are? I apologize in advance if I omitted some large piece of information. I do want the gun to be a repeater.

Thanks,
Josh

 

[FearNoWind]

Josh, with the information you've provided it's easy to imagine that the barrel is shot out with throat erosion, was reamed extra long, that your measuring equipment is faulty, that you'e confusing OAL with CBOL; the list goes on.
Let us know how you're measuring, what equipment you're using to take the measurements and what process (OAL gauge or a by guess/by golly fired case wiith a bullet stuck into the neck - which sometimes causes the bullet to drag on the lands and thereby generating a false reading).
Hang in there. Help is on the way.

 

[FURMAN]

As already stated we need more information but my guess is it was throated for a non VLD style bullet.

 

[NWPA0311]

As you guessed, I utilized a 190 grain Berger in a sized case. I then forced the bolt closed and removed the round. I could see the marks on the projectile where the lands made contact. Using calipers I measured the coal in order to obtain my coal that would have me touching the lands.

 

[Edd]

You can't use a Berger 190 gr bullet to determine what your OAL would be with a 200 gr ELDX.

Based on your measurements, I think you have a standard SAAMI chamber.

 

[J E Custom]

You can't use a Berger 190 gr bullet to determine what your OAL would be with a 200 gr ELDX.

Based on your measurements, I think you have a standard SAAMI chamber.

+1
But you need to know because it is controlled by the reamer used.

SAAMI chamber dimensions for the 300 WSM show that freebore is .189 A chamber cast is the best way to measure freebore. The case length is/should be 2.316.

If you try different bullets you will get different dimensions and the freebore length and throat will still not be correct.

Measuring COAL using a bullet will only tell you how far you are off the lands or when you contact the rifling.

J E CUSTOM

 

[WildRose]

As you guessed, I utilized a 190 grain Berger in a sized case. I then forced the bolt closed and removed the round. I could see the marks on the projectile where the lands made contact. Using calipers I measured the coal in order to obtain my coal that would have me touching the lands.

When you use the phrase, "forced the bolt closed" what did you mean? That's usually a really bad sign.

 

[NWPA0311]

When you use the phrase, "forced the bolt closed" what did you mean? That's usually a really bad sign.

When I was finding the coal to the lands I continued seating the bullet deeper and deeper into the case until I could barely close the bolt. I may have chosen the wrong verbage when I said forced. The bolt would just barely close when at the 3.0640 length with the Berger 190s. I will try some of the eldx and see what my results are. I still fear that the short action is going really be a limiting factor with finding an accuracy node with these bullets. All I can do is load some up and see how it shoots! If I don't get the results I'm looking for I may change the bolt face and rebarrel to a creedmore. Thanks for help this far.

 

[AZShooter]

I wouldn't worry too much about the jump to the lands. Load up the bullet of choice to cycle from the magazine and work up a load.


Weatherby rifles and a few others have yielded excellent accuracy with the bullet jumping a huge distance compared to your rifle. Some of the early Weatherby rifles use quite a bit of freebore.

Cartridge Throat length (free bore) copied from Weatherby's website under frequently asked questions:

.224 Weatherby Magnum .162
.240 Weatherby Magnum .169
.257 Weatherby Magnum .378
.270 Weatherby Magnum .378
7MM Weatherby Magnum .378
.300 Weatherby Magnum .361
.340 Weatherby Magnum .373
.375 Weatherby Magnum .373
.378 Weatherby Magnum .756
.416 Weatherby Magnum .239
.460 Weatherby Magnum .756
.30-378 Weatherby Magnum .361
.338-378 Weatherby Magnum .361


If it doesn't shoot to your satisfaction then move to a Berger hybrid. I would suggest to you that a hybrid WILL shoot with the jump to the rifling.

 

[Edd]

If you have a SAAMI spec 300 WSM chamber and you want the bullet to contact the lands and feed from a 2.970" magazine, you are going to need a bullet with a nose length of about .600". You won't have a lot of choices for a nose that short.

 

[J E Custom]

I wouldn't worry too much about the jump to the lands. Load up the bullet of choice to cycle from the magazine and work up a load.


Weatherby rifles and a few others have yielded excellent accuracy with the bullet jumping a huge distance compared to your rifle. Some of the early Weatherby rifles use quite a bit of freebore.

Cartridge Throat length (free bore) copied from Weatherby's website under frequently asked questions:

.224 Weatherby Magnum .162
.240 Weatherby Magnum .169
.257 Weatherby Magnum .378
.270 Weatherby Magnum .378
7MM Weatherby Magnum .378
.300 Weatherby Magnum .361
.340 Weatherby Magnum .373
.375 Weatherby Magnum .373
.378 Weatherby Magnum .756
.416 Weatherby Magnum .239
.460 Weatherby Magnum .756
.30-378 Weatherby Magnum .361
.338-378 Weatherby Magnum .361


If it doesn't shoot to your satisfaction then move to a Berger hybrid. I would suggest to you that a hybrid WILL shoot with the jump to the rifling.

Great advice and good information !!!

Most big cartridges have freebore that starts above .200 thousandths so the Weatherbys are not that bad especially if you are looking for velocity.

If you will notice, the dangerous game freebore is normally much more (378 460) Because of the use of round nose bullets that shorten the distance to the rifled bore. All/most others are normally
around .375.

I load all of my Weatherbys to mag length and have no pressure, velocity or accuracy with any of them. In fact when properly sized they are some of my most accurate rifles.

J E CUSTOM