7mm-08 questions I need thoughts new to reloading

LVJ76

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Bowhunter1287, 2650 FPS out of a 20” barrel would be a top end load IMO. I was getting 2710 FPS out of my 7-08 with a 24” barrel and the pedal was to the metal. What you currently have is a stout, very game capable cartridge. If it’s accurate run with it and don’t second guess yourself; my thoughts anyway.

Good Luck.

Agreed

Not knowing your OAL nor your mag length, at 2.875" the Amax bullet and 45g of IMR 4451 is compressed and at 2.875" the 162 ELD-x could and should be on the razors edge of compressed and you stated you can shake the powder in your rounds.

Please reply back with over all length. 45g of 4451 is a lot of powder to stuff in a 7mm-08 case with long bullets.

45.0gr is a Max recommended load as posted by a member here already. As another example the Sierra app shows for their 160gr TMK that at 44.9gr and a 2.80" COAL you might start seeing pressure signs. Yes different bullets but similar weight and just as a reference.

Now the powder still shaking at 45.0gr with this bullet weight makes no sense. Unless the bullet is sticking out more than recommended.



As a separate note, I don't see why the OP needs to try other bullets when he already chose what he wants to use.

To the OP, just run another test on paper and go from there.
 
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Deleted member 118518

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His COAL Is 3.000"
Or 2.921" LOL
 
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Deleted member 118518

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OK
SAAMI max pressure is stated as 61,000 PSI for the 7mm-08 REM. IMR Data for that cartridge with a 162 Gr A-Max is 45.1 Gr of IMR4451which gave them 2674FPS from a 24 inch barrel and yielded 58,600 PSI in the barrel they were using. That's a 2400 PSI cushion. In the barrel they happened to use. If you trust me with a calculator (you probably shouldn't) you will not reach 61000 (remember that pressure buildup is not a steady progression inside the barrel) psi until you put 46.94 gr of 4451 in the case and seat the ELD-X to a c.o.l. of 2.775" (Hornady's recommended col) or IMR seated the AMAX to a COL of 2.875" Which is where the 58,600 PSI is relevant. The OP is using 2.921" COL. Which could produce a slightly lower PSI in his barrel depending on how many barrels had been chambered by the reamer before it chambered his barrel. So, I do not believe that 2650 from a 20" barrel where you should, by rights, have a bit less pressure than that listed is consistent with reality. I would expect a velocity closer to 2525 to 2550 FPS from the 20" tube. If I may suggest something here. Take your electronic scale and zero it out then place 10 ELD-X bullets on it and record your weight. Then divide by 10 and see if you get 162.0 Grains or very near to that. If you do then the scale is most probably correct in what it's telling you. Assuming that the scale is correct then load 5 rounds with 45.0 grains of 4451 and chrono them. I will be very curious as to what the speed is. I assume that you are case trimming to 2.025"
 
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Deleted member 118518

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Don't get too hung up on compressed or not compressed. I have a custom 6.5 X 55 SE and the manuals show 46.0 grains of imr 4831 as max and that it is a compressed load but no it isn't. not even close.
 

Wachsmann

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So I hope to be around where your at with what I'm trying. I loaded up from a starting load at 43 or 43.5 to max load for a 168 grain ABLR with 6.5 starball. I'll be looking for pressure and also for grouping. I have about 30+ round to shoot for the spread I have. With the 47 grain charge I lost any feeling of shake in the case and the max was compressed or I could hear feel a slight crunch when seating. Its like 47.2 or 47.4 is max listed for the 168 bullets. Not a LRAB but a 168 SIE HPBT. If it was me I would repeat the load and if there are no signs of pressure, you can recheck everything, powder charge, etc, etc, but if it groups good. Get the gun out shooting at longer ranges and verify your drop data as to what your chrono is telling you for your speed. Chronographs can be off and not always exact. I had some astonishing results from one pound of RL 26 and 220 grain hornadys from a 300RUM. Shot at distance and realized my chrono was off by about 75fps. After truing up my load data I bought a new chrono. I now use a magneto speed. Its seem to be pretty accurate. And if it all turns out golden then get some practice in so you and your daughter will be ready when that buck walks out at a longer than normal poke. In my opinion 162's at that speed I'm setting sights on 600 to 700 yard pokes and probably just deer though. I wish I could find some 162 ELDX bullets also. I've not had good luck with LRAB in the past for as shooting tight groups but its what I found so I bought. Also Hodgons data claims 2776 out of a 24 inch barrel (max charge). I have a 22 so If I can get 2650 or higher and good groups I'll be happy.
 

LVJ76

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I'll be trying something similar in a few weeks.

In my Silhouette competition 7mm-08 I'll be trying the Sierra 160gr TMK with IMR-4451. I'll be starting at 43.0gr and work up to 45.0gr in 0.5gr increments to start, and if no pressure signs go further in 0.3gr increments.

It's a Rem 700 with a 26" Varmint barrel. I found close to 150 cases of Lake City brass that has only 3 and 4 firings that I had forgotten I had and pairing them with GM210M primers. I'll start .01 off the lands since it's a single loading rifle and see how it goes.
 
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