COAL

[El Torote]

I just received my Christmas present, a Savage 116 FCSS 300 WM, and could not wait to get started on some loads. However, I made a dummy bullet to measure to COAL and found it to be 3.545 with the 180 gr Barnes TTSX. (I place the bullet on an empty case, close the bolt, measure distance to barrel tip, then remove the bullet and measure. The difference between these two points is 3.545, .205 longer than book COAL).

Do these of relatively deep throats?

I am a little hesitant to burn money on developing loads on this gun.

Is this normal, or should I send it back to Savage?

Thanks

[jimbo88mm]

Welcome to the board.

This topic should probably be in the reloading (standard chambers) section and will probably be moved.


I'm sure someone here with more experience will chime in but the COL numbers listed in the manuals are conservative in the same way that published max loads are. These numbers are based on SAAMI specs. All rifles are unique but rounds loaded to SAAMI specs should work in every factory rifle.

I am at work right now so I don't have my manuals or my records with me but if I recall correctly, with my 243 stevens and 87 gr vMax, hornady calls for a COL of ~2.64. Using the method outlined by Ammosmith with the Lee neck sizer, I came up with a number of ~2.68.

Try this method and see what you get:

http://www.ammosmith.com/rifle-reloading/making-a-overall-length-gauge.php

Keep in mind that the longer you seat your bullet out the more pressure you will get in the chamber. It might be best to stick with a conservative COL and find where your nodes are. Once you found the best load then you can start tweaking bullet seating depth.

[El Torote]

I check this way too, however find the rods a little more accurate, since the bullet get pulled a little sometimes on extraction.

My concern is that I am .205" longer than SAMMII COAL for the .300 WM on a brand new rifle. Which may be fine for longer bullets like the barnes ttsx, but may not be enough neck contact for a Sierra Gameking or Nosler Partion bullet.

[tammons]

I dont know the sammi chamber specs for the 300 wm, but if you are trying to shoot target with it I would single load them long.

If hunting and trying to do something special like jump that bullet .020 at factory magazine length you might need a custom chamber. Other than that you will need to jump them and shoot them.

Most savages have a fairly long freebore.
Actually with most I have owned with a bullet touching the lands the col
will be longer than mag length.

I would imagine the longer freebore in the 300 WM is for round nose bullets and maybe to keep the pressure down. I bet if you load a roundnose bullet to 3.35 it will be pretty close to the lands.

I have a 458 WM barrel that has something like an extra 3/4" of freebore at mag length.
Dumps the pressure and FPS way down. The only bullet I can use that will touch the lands and still be even in the neck at all is a 600 gr roundnose.

[El Torote]

tammons,

Yes, I intend to develope loads with barnes 180 ttsx. For my 7mm Rem Mag nd 338 WM, I found it best to jump the lands at about .06.

That would put my COAL at 3.485 vs 3.34.

My 338 wm are loaded from 3.38 to 3.40 for Sierra GK and Barnes TTSX respectively.

Just a little concerned over the .085 on the 300 WM. Never had a Savage before, so do not know how deep the throats are expected to be.

[tammons]

Its pretty typical of savage barrels that with a spitzer bullet you will not be able reach the lands at magazine length, except for the shorties loaded long like 223, 6mmBR, 25 wssm etc.

I have had a number of barrels 375 ruger, 338-06, 7mm-08 among others and non of them would touch the lands with the cartridge at magazine length.

Have a 308 now I hunt with a lot with the 208 gr amax and it wont touch the lands either.
I dont even think a 220 gr roundnose prohunter will reach the lands.

[blom]

Another thing to keep in mind, the Barnes bullets are all copper, making them longer than a standard jacked bullet. As long as you have enough bearing surface in the neck which you should easily have I wouldn't worry about it.

[ecountry411]

I just experienced the same thing with an Edge 308. My reloading manual showed the catridge used was 2.78 for 178gr Hornady A Max but after shoving my bullet in the brass with the bolt it seated at 2.890 I set it down 3 thousandths more to 2.887 It wasn't touching the lands. I gave it 10 thousandths more and my COAL is 2.877 vs what the book had at 2.78, BIG difference.
From what I understand the minimum OAL is the measurement that is important. NEVER go under that. If it is over it's no big deal as long as the bullet is seated good in the brass and it will feed from your clip.

[Warthog]

You probably already know this, but there is not a direct relationship between COL and throat depth. The bullet profile can make a big difference. I took the following measurements with my Hornady OAL Gage on my Savage 10FCP and Browning BLR, both in .308. Notice the Barnes bullet.

Savage
.308 Max CART = 2.810 Max Savage Magazine = 2.970
30 Cal Bullets Average
Barnes 165 gr Banded Solid 2.727
Hornady 110 gr V-Max 2.767
Hornady 130 gr SP 2.673
Hornady 155 gr A-Max BTHP 2.829
Hornady 178 gr A-Max BTHP 2.761
Sierra 135 gr Match King HPBT 2.832
Sierra 168 gr Match King HPBT 2.814
Sierra 175 gr Match King HPBT 2.810
Sierra 200 gr HPBT 2.814
Sierra 220 gr Match King HPBT 2.833
Nosler 175 gr Cust. Comp. HPBT 2.797


BLR
.308 Max CART = 2.810 Max BLR Magazine = 2.780
30 Cal Bullets Average
Barnes 165 gr Banded Solid 2.905
Hornady 110 gr V-Max 2.848
Hornady 130 gr SP 2.754
Hornady 155 gr A-Max BTHP 2.912
Hornady 178 gr A-Max BTHP 2.896
Sierra 135 gr Match King HPBT 2.928
Sierra 168 gr Match King HPBT 2.903
Sierra 175 gr Match King HPBT 2.900
Sierra 200 gr Game King HPBT 2.907
Sierra 220 gr Match King HPBT 2.922
Nosler 175 gr Cust. Comp. HPBT 2.892


In .308 the Savage throat is much shorter than the BLR. Also the Savage magazine is longer (2.970 vs 2.780). In some bullets I could easily be into the lands, which could cause pressure issues. I think this is why some manufacturers have long throats. If the throats were short enough to engage the rifling with store bought 2.810" bullets, some might not close, and some might have pressure issues.

The bullet stops when the diameter of bullet = the diameter of the barrel. There are Bullet Comparator Kits which fit on the dial calipers which have inserts with holes the same diameter as you lands if you want to measure exactly where the throat ends, rather than the COL. It will also measure the bearing surface of a bullet with a flat base. Two will allow you to measure the bearing surface of a boat-tail bullet.

The gages cost a little, but they really are really worth it. Savage probably knows what the throat depth should be, but the COL measured for a particular bullet will not tell them much.

[GaCop]

Once you determine max OAL to the ogive with a Hornady OAL or other guage for each bullet you'll load, the book lengths to the tip become meaningless. If your loading for a hunting rig your stuck with the max mag box length to feed properly.

[RKG]

. . . .
Keep in mind that the longer you seat your bullet out the more pressure you will get in the chamber. It might be best to stick with a conservative COL and find where your nodes are. Once you found the best load then you can start tweaking bullet seating depth.




Not quite. Up to a point -- which is just shy of the bullet touching the lands upon chambering -- lengthening the COAL will actually reduce peak pressure (albeit only slightly). This is so because -- with the same caveat -- lengthening COAL increases combustion chamber volume upon initial ignition.

A pressure spike is possible at the point of lands contact (or beyond that point, which is called "jamming") because doing this spikes the resistance of the bullet to initial movement down the bore, which, in turn, delays the increase in combustion chamber that results from the bullet's movement down the bore.

[El Torote]

I finally had good enough weather to break in a Savage 116 FCSS 300 WM, 24"bbl. I used Federal Hot-Cor 180s to break in the barrel.

Then proceeded to fire 2 ladders of handloads, 180 gr Barnes TTSXs and 165gr Hornady SSTs.

At a Barnes listed max charge of 72.5gr RL-19, vel was 3091fps (adj for dist. to chrony), 56 fps faster than the book velocity. Seems ok, however I felt too fast because the rifle has a very deep throat (COAL 3.53 measured vs 3.34 book) and the rounds were loaded for a .06 jump at 3.47 COAL. Extra space, less dense, should be a little slower

The Hornadys were loaded with IMR-4350, and came in slightly lower than book for the charge; 70gr @ 3060fps vs 3100fps @69.8gr book. This was expected, since the hornadys measured 3.47 COAL, and were loaded at 3.45 for a .02 jump.

Since both bullet brands measured way longer, but one was faster than book (surprise) and the other slower (expected), I then proceeded to chrony the Federal Hot-Cor 180 factory loads; they averaged 3089fps vs. 2960 listed on the box!

Temp 58 deg F, elevation, 5000ft, wind, none for handloads, about 10 mph slightly angled from head-on.

Chrony was straight, level, 24ft from barrel.

What up?