Home Forums Reloading Big Game Rifles Reduced loads using 4198

I am interested in reduced loads for my Winchester 70 in 270W. I have learned much from the info contained in this thread (especially by Seafire, who has a long history of doing this). So, first off, I wish to thank all of you who took the time to provide input. I have copied this entire thread and put it in my reloading notebook. I have both IMR 4198 and H4895. I plan to first try reduced loads, using the Hornady 130 gr SST with these powders. My goal is to achieve a MV=2400 - 2500 fps. My Model 70 rifle has a 20" barrel. I do, however, have 2 questions both concerning the COL of the loaded cartridge:

When using IMR 4198, what COL should I use? I ask this because I understand that reduced loads with IMR 4198 really means reduced velocity - not reduced pressure. The info, relative to this is as follows:
The only reload manual that I can find listing IMR 4198 for the 270 W is Lee's Modern Reloading Manual (2nd Ed), where the "Minimum" COL listed for this powder and generic 130 gr jacketed bullets is 3.250" with recommended loads from 31.9 grs = 2481 fps to 35.5 grs =2660 fps. In Hornady's Reload Manual #9, the COL listed specifically for their 130 gr SST is 3.210", though IMR 4198 is not included in the powders tested. Finally, the COL in my rifle for this bullet just touching the lands = 3.335" (cartridge base to bullet tip). So, given this info, what would be a safe range of COLs? Hornady's COL is .04" shorter than Lee's "Min" COL, though Lee's data is not specifically for the 130 gr SST and Hornady's data does not include IMR 4198.

The last question is COL for H4895, for which I know Hodgdon recommends starting reduced loads at 60% of "maximum" load listed. Hodgdon online data exists (thankfully) for the 130 gr SST using H4895 (COL=3.235"). Lee's 2nd Ed. Manual lists "Minimum" COL = 3.280" for generic 130 gr jacketed bullets using H4895. In this case I "assume" that I should use Hodgdon's online data but how much could I safely vary the COL to achieve optimal seating depth, given that Lee's "Minimum" COL (3.280") is significantly longer that the COL listed in Hodgdon's online data (3.235") or even in Hornady's Manual #9 (3.210"). Once again, the COL of this bullet just touching my rifle's lands = 3.335".

Thanks for any input you may have. I may be over-thinking this but, regarding reloading, I believe that the only stupid questions are the ones you don't ask.

You are way overthinking it.

Start your load development with the bullet as far out as you'd want to try it. Once you've established a safe charge you can work the bullet back shorter as that will lower pressure.

Mathman, Thanks for the response. Yeah, I tend to overthink things. I will use the IMR 4198 data listed in the Lee Manual but is there a point, where working the bullet back shorter will start to increase pressure?

Yes, but you'll probably not get anywhere close to that.

Good. Thank you for taking the time to answer my inquiries.

I'd be looking at a Lyman Cast bullet manual...either Number 4, which is the current one

or the Number 3 which would probably be findable at larger used book stores... I have bought a couple of copies over the year for like $3.00.

the first one just wore out....so I replaced it...

I wouldn't worry about reload manuals not listing a bullet you desire to use.... just be concerned about its weight...

2400 to 2500 fps shouldn't be a hard accomplishment....

I normally simplify this by using a charge of 30 grains of 4198, whether in a 308 sized case or an 06 sized case....

get your MV over a chrony, and on trajectory charts, you can figure out what a point blank range is...

Normally using this, and especially working with kids via Boy Scouts.... set a zero at 3.5 inches high at 100 yds, you should be about right on at 200 yds, and 3.5 inches low at 230 to 240 yds, when using a spitzer bullet... and you don't need the heaviest bullet use.. I use 150 grainers, vs 180s in an 06......its never failed me...

with the above info consider the facts... 90% of all game is taken within a 100 yds... and 95% is taken within 200 yds...

what more do ya need...and recoil is so much lower...

I don't recommend or use reduced 4895 loads... they give too loud of a retort/ kaboom, for what you are using... that intimidates a lot of kids and female shooters...and the noise make them think that load has more recoil.. it really doesn't...

at the same time, I find H4895 loads are finicky for accuracy... I see much tighter groups using IMR 4198 than H 4895...always have..

substituting IMR 4895 for 4895 loads, results are better, more accurate and less retort/ kaboom, is what I have always found..
and that is not just only for myself... but moreso working with kids and some women shooters feeling the same results..

accuracy? accuracy is accuracy... Reduced IMR 4895 loads yield better results than Hodgdon/ ADI loads...

H 4198 is more accurate than H4895, but IMR is more consistent in my book...

Seafire, Thanks for your response. You (and Mathman) have forgotten more than I will probably ever know. I do have H4895 but, based on your advice, I will use IMR 4198 (which I have more of anyway) for reduced loads. Once again, thank you for sharing your knowledge gained by experience.

I will get Lyman's 4th Edition Cast Bullet Manual. It is currently out of stock at the local Sportsman's Warehouse but I'll find a copy.

Another thanks from me, great info. I have a good supply of IMR-4198, so far mostly used in the 45-70 & light bullets in the 223s.

Yes, I do take a peek at reliable net data or manuals before loading. I think it’s in the Marlin forums, bookoo older manuals & data for free downloads.


https://www.marlinowners.com/threads/on-line-free-load-data-and-references.281290/

What about 125 grain bullets in the 308? Max somewhere near 35 gr 4198?

I just did some interpolation of the IMR4198 data in my old, tan IMR powder booklet. Reverse engineering what is shown for 110, 150 and 180 grain bullets suggests a max load for a 125 being just under 37.5 grains. This would have been for eighties vintage powder.

Hodgdon's online data suggests to me that H4198 would be OK there too.

Diclaimer: This is not tested data and I'm not telling you to use this information. What if anything you do is on you.

Well the Remington reduced load is supposedly 36 grains per seafire. So that is in line with what I was thinking. Thanks.

That may have been for the 30-06, not the 308.

Maybe but if you are seeing 37.5 as max, the 36 should be safe and comfortable to shoot

I shot the old IMR booklet max of 35.5 grains under a 150 and it was quite safe in my rifle. Easy bolt lift and extraction.

Thanks