In order to participate in the GunBroker Member forums, you must be logged in with your GunBroker.com account. Click the sign-in button at the top right of the forums page to get connected.
Options
Anyone wanna run some quickload for me?
JustC
Member Posts: 16,056 ✭✭✭
I need pressures (estimated) for several powders in the 300RUM.
I have a case cap of 114.6gr h20 to the top of the neck
rem brass
210M primer
30" 1:10 twist 5groove tube
I need it run for 220gr and 240gr pills using H1000, RL25, and Retumbo as well as maybe N170 or any of the N series slower powders.
Just trying to get a jump on finding a new load without buring up too much of the match life.
Thanks if anyone has this kind of data and time.
I have a case cap of 114.6gr h20 to the top of the neck
rem brass
210M primer
30" 1:10 twist 5groove tube
I need it run for 220gr and 240gr pills using H1000, RL25, and Retumbo as well as maybe N170 or any of the N series slower powders.
Just trying to get a jump on finding a new load without buring up too much of the match life.
Thanks if anyone has this kind of data and time.
Comments
I'll plug in some numbers this evening (don't have the programs on my work computer).
Anything you have is better than my lack of a program.
I think that 20N29 or 24N41 might be slow enough or maybe too slow?????
You'll find that 24N41 will work almost O.K. with either the 220 SMK or the 240 SMK and a nearly full case (98%). You will be near the top end of 2950 to 3050 FPS., lighter faster, heavier slower obviously. 20N29 will need a compressed load and lacks some efficiency. The N-170 will only get you up around 94% and 2975 FPS approximately. All the other suitable powders will be in the 92-93% case capacity range and with similar velocities. I didn't have good results from Retumbo.
Have you looked into some of the surplus powders yet?
Best.
ADDED:
I guess I should have added that I run my .300 RUMs at approximately 62,000+ PSI and not all the way to the top of 65,000 PSI. My accuracy is better in the low to mid-60's range with the 220's and the few 240's that I've shot.
220SMK
N203-B Safe 69.2/3010/54850 to 76.0/3160/63625 Caution 76.5/3170/64325 Danger 76.9/3180
N165 Safe 69.9/2645/56950 to 77.1/2775/64400 Caution 77.3/2780/64750 Danger 77.6/2790
RL-22 Safe 84.3/3020/54300 to 92.8/3170/64100 Caution 93.1/3175/64325 Danger 93.7/3185
N170 Safe 75.9/2780/56125 to 82.0/2890/62350 Caution 82.8/2905/63100 Danger 84.4/2935
Retumbo Safe 85.7/3005/54200 to 92.5/3130/61700 Caution 93.5/3145/62875 Danger 95.2/3175
H-1000 Safe 81.9/2806 to 89.6/2995 Caution 90.1/3005 Danger 91.0/3020
240SMK
N165 Safe 65.1/2395/57600 to 71.8/2518/64420 Caution 72.0/2520/64650 Danger 72.3/2525
RL-22 Safe 85.3/2920/53950 to 93.0/3055/62675 Danger 93.2/3055
N170 Safe 73.4/2640/56275 to 79.2/2747/62300 Caution 80.0/2760/63200 Danger 81.6/2790
Retumbo Safe 87.8/2950/53350 to 94.2/3060/60625
H-1000 Safe 79.5/2665/55550 to 87.1/2791/63510 Caution 87.5/2795/63950 Danger 88.4/2810
Using this program, I ran some W-748 through my -06 with a 150gr NBT. The program was off by about 75fps, but OTOH I fired 5 shots at the top load and got a AVERAGE of 3162fps with a 40fps ES (not to shabby a speed for a 30-06).
I visited with Dave Manson last Friday, and ordered my 300 Tomahawk reamer and HS gauge, estamated delivery time is 8 weeks.
tailgunner, have you found the data to be pretty close from the program as far as pressures are concerned? like does a sticky bolt appear when the program indicates it will after a jump past the danger mark??
nononsense,..what powder would you start with??? I went to retumbo because of it's slowness, slower than RL25 and H1000. I had a great load with the 200gr SMK and 88.0gr H1000 (max in my chamber if that gives you an idea of how tight and short throated it is) but I wanted more bullet and less empty space. I guess you mean WC872??? how does it burn??? H870 looked like a fireplace chimney after only a few rounds,..never could get that crap to burn decent,...sloppy groups and poor velocity,..but the can was old even though it had not been opened. maybe it was bad???
I didn't get good results from Retumbo but that doesn't mean that you won't. If you have it on hand you may as well load some up and give it a try. Others have noted good success with it and you might also.
Other powders to try would be Hodgdon's US869, WC860 (surplus) and AA-8700. I wish that Ramshot had another powder slower than Magnum then we might really have something.
I have worked a little with the 24N41 but the hesitation that I have stems from the description of your chamber and how it responds to volume and pressure.
What is your OAL with these 2 bullets? Are you planning to load singly or from the magazine?
Best.
ADDED:
Sometimes I have to re-read some posts just to try to fill in some of the blanks for myself.
This is just a thought for consideration:
Maybe what you need is a slightly "looser" chamber with a longer throat that could accommodate some of the powders and bullets at a slightly reduced pressure level. I don't mean to imply sloppy but merely a little less tight on the top end of the chamber and maintain the closer tolerance at the head to control expansion there. The longer throat is obvious. Maybe a little more leade for a slightly better pressure drop... Call Dave Kiff and see if he has some time to discuss this with you.
I had Kiff run me a Match reamer but only considering the throat and the head. I left the top portion of the cartridge a little more generous per the cases I had for measurement. This is a huge case and we're not talking about measuring to tenths of thousandths for a 5-shot group to determine a winner like the point blank guys. Maybe a little more generous chamber and slightly tighter neck on the case to promote better burning... These things can keep me awake at night...
Best.
They note that there is a 1:10,000 chance of exceeding max pressure before the "caution" charge is reached, and a 1:100 chance with the "danger" loads. It's in the form of a bar graph, I gave the numbers for the bottom/top of the "green", top of "yellow" and top of "red" (this being the spec'ed pressure limit)
With the load mentioned above, the bolt lift was smooth on 3 of 5, and slightly sticky on the other 2. Primers (WLR) were definatly flat on all of them. I'm used to having the WLR primers flatened on this rifle (my goto load is 61.5gr of RL-19), but these were a little flatter than I'm used to seeing.
nononsense, I'll measure them tonight and let you know the OAL, I have 216gr clinch rivers loaded, but if after one more try Greg doesn't have any for me to buy, I will be leaving for something along the lines of the 210gr berger, 220smk, 240smk, and any other pills in that range you may suggest.
I single feed these onto the score high BR follower, no magazine in the ole Tooley handle[;)] This is at this point, my official 600-1000yd rig.
thanks
It may have been that particular lot number of Retumbo, I don't know. It was inconsistant and slightly dirty by comparison. But the end result is that I could do better with other powders. You know as well as I do that the number of variables present in any of these rifles and chambers is huge when it comes down to analysis of errors or deficiencies. So it's possible that some additional tuning may have helped but I didn't want to waste the time and money when I had powders that worked better in place already. Schedules and budgets sometimes set the process.
I still have the canister so I may decide to drag it out for a line of testing again at some point. Don't let one slightly sour report put you off from testing it though as it might prove to be your winning combination.
I hope Greg comes through for you with bullets. I know it's tough to create all of his production in sequence and still keep everyone happy.
Keep us up-to-date on your progress.
Best.
without trimming the meplats, the OAL is ~3.707-3.712"
the distance from casehead to ogive is 4.070 - .997" (sinclair comparator height) = 3.073" - .005" jamm seat = 3.068" casehead to ogive at the lands for the 216gr clinch rivers.
114.6gr water cap to top of neck.
sound like a reamer you may be familiar with? If so, what did that one like[;)]