300 Tejas

[Ryan55555]

Can't seem to find much info on this round. Does anyone have any experience with it?

I believe it is a 300 RUM improved with a 50 degree shoulder.

Is it that much of an improvement over a 300 RUM?

How much more case capacity over a 300 RUM?

Is brass life better / worse?

Any info would be great.

 

[MN Hunter]

Ryan55555

There is a member here that I had the pleasure of hunting with last fall that I believe has a rifle in this caliber. The more I think about it - it may be a 338. Tejas. You can try shooting him a PM.

7STDUBBERU

 

[slush]

The 300 Tejas is Brad Stairs round. His shop is Wasatch Precision Arms in Ogden Utah. I think he is one heck of a gunsmith. I have had three rifles built but not in the 300 Tejas. I do believe it's off a 300 RUM case. You can also go to Shooters Oasis.com under gunsmithing There is a comparison on the 300 Tejas.

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[FEENIX]

Can't remember where I read it but I think .300 Tejas is like a .300 Weatherby improved. Or is it .300 RUM AI?

 

[338 bruce]

I have a 375 tejas and it shoots a 300 grain bullet at 3200 fps with 111 grains of imr 7828ssc and 350 grain smk at 3000 fps with 108 grains of rl25 from a 31" brux barrel.

 

[Fiftydriver]

338 Bruce,

What is the parent case for your 375 Tejas. From your powder charge I would suspect its on the big Wby case or something similiar. Are those actual chronographed numbers or estimates?

Only reason I ask is because even the 378 Wby will fall WELL short of the velocity your reporting with max loads.

Just curious.

 

[johnnyk]

Wouldn't that be considered light artillery? JohnnyK.

 

[7STDUBBERU]

Ryan55555

There is a member here that I had the pleasure of hunting with last fall that I believe has a rifle in this caliber. The more I think about it - it may be a 338. Tejas. You can try shooting him a PM.

7STDUBBERU

Good memory buddy,

I do have 338 Tejas, it is a 300 RUM necked up and the shoulder blown out to 50*. This rifle is also built by Brad Stairs but this is marked Performance Guns. Brad is a good guy and gave of his time freely when I called him for his opinion on this rig prior to buying it from it's original owner. If you would like his phone number PM me and I will forward it to you.

Getting 2880FPS with 300 gr SMK's with exceptional accuracy. This rifle is a shooter.

 

[MN Hunter]

Nice picture
That rifle looks as sweet as I remember it.

 

[Fiftydriver]

I have played with a couple round with shoulder angles over 40 degrees and in every case ran into problems when the brass got a few firings on them with high pressure loads. The shoulders would collapse when they needed to be bumped to set the shoulder back very slightly for proper chambering.

With moderate loads this was not as significant but it did still occur but to a lesser degree.

One was a 7mm on the 8mm Rem Mag case with a 50 degree shoulder and that rifle has some serious issues with pressure variations. You likely would never see this with a 338 cal and likely not with a 30 cal but I simply do not like a shoulder that steep

It sounds like the 338 Tejas is identical in performance with the 338 Edge so personally I would not want to deal with the issues of the 50 degree shoulder for no real improvement in performance. The 338 Edge will get you 2850 fps to 2900 fps with the 300 gr SMK and there is no fireforming needed.

If the 300 is the same as the 338 but necked down to 30 cal, it would seem to reason that it would be basically the same performance as the 300 RUM.

Not saying they are not good rounds and I am sure the rifles are very good quality and good shooters but I just do not see alot of advantage improving a case that is already pretty well improved in design other then a sharper shoulder. This is why the performance increase is not significant over the parent case.

Just my opinion, not trying to flame anyone, just saying what I have found using cases with shoulder sharper then 40 degrees.

 

[jeff 300]

I have played with a couple round with shoulder angles over 40 degrees and in every case ran into problems when the brass got a few firings on them with high pressure loads. The shoulders would collapse when they needed to be bumped to set the shoulder back very slightly for proper chambering.

With moderate loads this was not as significant but it did still occur but to a lesser degree.

One was a 7mm on the 8mm Rem Mag case with a 50 degree shoulder and that rifle has some serious issues with pressure variations. You likely would never see this with a 338 cal and likely not with a 30 cal but I simply do not like a shoulder that steep

It sounds like the 338 Tejas is identical in performance with the 338 Edge so personally I would not want to deal with the issues of the 50 degree shoulder for no real improvement in performance. The 338 Edge will get you 2850 fps to 2900 fps with the 300 gr SMK and there is no fireforming needed.

If the 300 is the same as the 338 but necked down to 30 cal, it would seem to reason that it would be basically the same performance as the 300 RUM.

Not saying they are not good rounds and I am sure the rifles are very good quality and good shooters but I just do not see alot of advantage improving a case that is already pretty well improved in design other then a sharper shoulder. This is why the performance increase is not significant over the parent case.

Just my opinion, not trying to flame anyone, just saying what I have found using cases with shoulder sharper then 40 degrees.

My 338 edge you built is shooting a 300 smk @ 2950 with 93.5 of h1000 with 32" barrel

 

[338 bruce]

my 375 tejas was chronographed on a shooting chrony

 

[Fiftydriver]

338 Bruce,

So your saying your getting 3200 fps with a RUM based wildcat with a 300 gr bullet, or is the 375 version based on a larger parent case?

 

[338 bruce]

it is a 375 rum case based wildcat