I am new to the forum having just recently found it.  What a great resource!

I have an 1898 Krag that was sporterized a long time ago, I bought it about 15-20 years ago.  I have shot nothing but Winchester factory 180 gr spitzers through it.  I am wanting to reload for it, and want to load it down just a bit.  I would like to use Winchester 748 powder, as that is what I reload my .30-30 and .45-70 with, don't want too many powders around.

I also would like to load it with 170 gr flat nose bullets (.30-30 type) mainly because I want to limit velocity to about 2100 fps to take it easy on the old girl, but still be good as a deer rifle.

Does anyone have a load or a resource that gives data for reloading with W748 and 170 gr bullets?  Any info with the 748 powder would be great, I can reduce it a little if anyone loads a 165 gr bullet.  I found a site (referenced by someone here) that shows a starting powder charge of 32 gr of 748 for 165-168 gr, thought I may start there.

Thanks

The published data is what I don't have.  I have the Speer #12 manual, it shows load data for several powders, just not the 748.  I like that powder so much for the other reloading I don't want to change those.  It works so well for the .30-30 and .45-70, I figured it would be great for the .30-40.

I was really just looking for .30-30 type performance, so recoil shouldn't be an issue.  I figured a 165 gr spitzer at 2000-2100 fpswould have a hard time expanding, that's why I was looking at the 170 gr FN.

I like the sound of that 165 spitzer load you mentioned, at that speed I wouldn't need to worry about using the FN bullets.  I also don't like the idea of winging it, so I may just have to find a different powder (like the IMR 4064 you mention)

I contacted Speer, who steered me toward Hogdon and I'm waiting to hear back from them now as far as load data for the 748 powder. 

Funny, I was thinking about selling the Krag, but now that I've found this site and dusted it off I have all kinds of plans for it

One thing to keep in mind is burn rate for the chosen bullet weight.  IMR 4064 is great with the 165 and even 180 grain bullets, but burns too fast for a heavier bullet like the 220 grain.  The powder would be spent before the bullet is 3/4 down the barrel, which means that 1/4 of the barrel length, the bullet is slowing before it reaches the muzzle.  Likewise, a slower burning powder like 4350 with a lighter bullet, the powder is still burning when the bullet leaves the barrel, which results in poor accuracy and performance.  I don't know the burn rate for 748, but if it performs well in 30-30 with a lighter bullet, then it should be ok for a lighter bullet in the Krag also.  I'll take a look at my Hornady and Lee charts to see if 748 is listed, and if so, I'll post the data for you.

Paul

Like most spherical rifle powders, W748 can be more difficult to ignite and burn well at low density than tubular powders (which achieve progressive burning primarily by granule geometry rather than deterrent coating). That said, 748 isn't as heavily coated as some of the slower numbers and generally does OK at medium loading density. Magnum primers may help.

I wouldn't expect great performance from any medium rifle powder at density below about 60%, but the QuickLoad estimates below show reasonable burn performance at densities from 62 to 79%, all at acceptable Krag pressures.

Cartridge          : .30-40 Krag
Bullet             : .308, 170, Hornady FP 3060
Cartridge O.A.L.: 3.089 inch or 78.46 mm
Barrel Length      : 30.0 inch or 762.0 mm
Powder             : Winchester 748

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% of nominal charge.

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
%       %    Grains   fps   ft.lbs       psi         psi      %          ms

-20.0    62    32.00   2083    1638   21558   4414     92.4    1.992
-18.0    64    32.80   2129    1712   22768   4543     93.3    1.948
-16.0    65    33.60   2175    1786   24043   4668     94.3    1.905
-14.0    67    34.40   2221    1862   25389   4788     95.1    1.864
-12.0    68    35.20   2266    1939   26806   4905     95.9    1.824
-10.0    70    36.00   2312    2017   28299   5016     96.6    1.785
-08.0    71    36.80   2357    2096   29873   5122     97.3    1.748
-06.0    73    37.60   2401    2177   31533   5223     97.9    1.711
-04.0    74    38.40   2446    2258   33283   5318     98.4    1.675
-02.0    76    39.20   2490    2340   35128   5407     98.8    1.640
+00.0   78    40.00   2533    2423   37075   5489     99.2    1.606
+02.0   79    40.80   2577    2506   39129   5565     99.5    1.569

Note how the "Prop.Burnt" percentage increases as charge and density are incremented.

psteinmayer wrote on Mar 8^th, 2013 at 2:55am:

This assertion sounds logical but may not be accurate. Graph below shows predicted burn curve of two 220 gr. loads giving virtually identical velocity and pressure. If the modeling is accurate, 4064 is some 99% burnt in the 30" barrel, while 4350 (with its larger granule size) has left about 8% unburned.
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Modeling software like QuickLoad allows us to hold some of our logical assumptions up to mathematical scrutiny. It's not a perfect tool, but often better than accepting assertions with even less support.

While I am NOT a ballistic technician in even the crudest sense, a factor which immediately struck me was the apparent very slight difference - at least in this example - between 22" and 30" of barrel length. Thanks, Parashooter.