I have a mid 70's tang safety, M77, in 257 Roberts.
I'm trying to work up some loads for this rifle.
With the Nosler 110 grain Accubond, I have an OAL of 3.210" to the lands.
With the Nosler 115 grain Partition, it's 3.175" to the lands.
This seems like a long ways to the lands. I bought the rifle used.
Are Rugers throats this long? or do I have major throat erosion?
Anyone else finding this length to the lands?
Thanks, Dave

My Roberts has 3.070" to the lands with the 110 Accubond, so yours is long throated compared to mine. I doubt it is throat erosion and probably was built by the factory that way. How is the accuracy of the rifle? As long as it shoots fine, I wouldn't think twice about the long throat.

I bought the same rifle in 1972. I'll check it out and let you know later. roger

I was getting 2" to 3" groups with these bullets.
However, my OAL was 2.850.
I'll try these loads again, only closer to the lands. I'll test when it stops snowing.
Thanks

The OAL measured 2.903" using the Sierra 90 grain HP. The rifle is the Ruger Varmint tang safety bought in "72". roger

My reloads for my m77 Ruger .257R were engaging the rifling with Hornady 117's and 100grn TTSX's if loaded over 2.94" OAL.

I'm good between 2.779-2.88" with Hornady 117's, and 90grn Sierra hpbt.

I don't have a Ruger M77 in .257 Bob but the throat on my Winchester M70 Featherweight is longer than the magazine will allow. The throat on yy Ruger #1B is also quite long, much longer than I feel is necessary.
Paul B.

My custom Pre 64 M70 was chambered by Krieger and the 110 Accubonds sit against the lands @ 2.873". The 115 BT run 2.917".

Alan

Having a longer throat has many advantages...you can seat the bullet out farther and gain more case volume which translates into higher velocities and energies.

I have 3 Tang Rugers that will handle COL's of around 3.32" so you are in luck.

I don't know how long the 110 AB is but...if you measure a few and post the lengthd I will run the numbers through LD or you can do the same on Powley Online, http://kwk.us/powley.html. It will give you some idea how much "extra" you have.

Another thing is a long throat could be considered as "Weatherby-izing" your rifle. You can gain extra velocity by loading slightly heavier charges due to the pressure reducing action of the "freebored" longer throat.

My 338-06 has a "freebore" of ~0.600" due to the smith throating for the discontinued Speer 270 gr bullet plus a bit more. I need ~4 extra grains of 4320 just to equal published recommended loads and I have increased the powder charge an additional few grains to gain ~100 fs more velocity over published loads...

ALL SAFELY...no pressure signs and the cases can be reloaded well over 10 times which is MY limit for reloading that sized case.

Luck

When someone uses AB with respect to bullets now days, I take it they are not refereing to the old AB bullet manufacturer, or are they? roger

quote:

I have 3 Tang Rugers that will handle COL's of around 3.32" so you are in luck.

IIRC, the early Ruger 77's in .257 Roberts used the full length action, while later ones used the medium action. There would very likely be a difference in how they are throated. If you have the long action/throat, seat those bullets OUT there! This gives you more velocity for less pressure, and seating near the lands most frequently provides better accuracy than bullets that have to make a long jump in the throat.

I have a pre-64 model 70 that oal is 2.8, I was thinking of having the throat lenghtened to where 120 grain bullet would be flush with base of neck, I've read of this and replacing box with 06 box (also need short box for 243 barrled action)this is similiar to ackley improved in volume of power gain.Has anyone done this , I realize i'll have to change the extractor collar to gain the longer bolt throw.

You'll probably gain 50fps or so.

But be aware, you will destroy the rifle's collector value, if that is important to you.

I had a 70's 77 in .257 and it had a long throat, but it was great for hanging long bullets out the end of the cases. the rem 700 was based on a short action and when you made the bullets long enough for accuracy, they wouldnt fit in the magazine box because they were too long. both the 7x57 and 257rbts in the R77 were built on long actions. My buddys 77 in 7mmx57 had such a long throat it wouldn't spit anything out accurately except for long 175 grain pills. I told him to have the barrel turned in for 140-150 grain bullets but he said hell with it and sold the gun.