Question for the reloading experts...

[Scott CWO]

I am not a reloader and not all that knowledgeable about reloading. Need some advice.

I've got a couple custom rifles built by a client/friend who trained under David Miller of AZ. The builder also supplied me with custom ammo for the rifles and I am about out of it. One of the rifles is a stainless .338 WM built on a Winchester M70 action with a fluted Krieger barrel. It's topped with a Leupold scope with Premier Reticle dots at 300, 400, 500 and 600 yards. The rifle was designed for high-country elk hunting in mind. The dots were aligned on the crosshair based on custom load data with Swift A-Frame 225 grain bullets at 2900 fps with a BC of .384 and environmental factors of 45F temperature and 8500 elevation.

Since I am about out of the ammo, I was talking to another guy about the load to see if he could replicate it. I told him the load details were 70.5 grains of IMR 4350, Federal 215 large magnum primers, WW brass, 3.30 OAL and 2.49 case length, as provided to me by the builder. I was told by the new guy that this load would be about 70,000 PSI and about 6000 PSI over the SAAMI max of 64,000. He also said it was probably a compressed load. I didn't know it was that hot of a load. Is this correct?

When the builder made up the rifle and ammo, he told me he had tried loads spanning from 69 grains all the way up to 71.4 and settled on the 70.5 grains as the most accurate. If 70.5 is past SAAMI, 71.4 would be much higher I think?

I haven't experienced any problems using the 70.5 grain load. I was hoping I could get a custom ammo maker to make me something close but I am wondering if anyone would if the pressure is really 70,000 PSI.

Does anyone out there have experience with driving a 225 grain A-Frame to 2900 fps, or at least 2850? My fear is that if I drop down in velocity much, the dots in the scope will be meaningless. Are there new powders that can get to 2900 fps with less pressure?

 

[JimP]

What needs to be done is for your new supplier to work up the loads since he will be using a different lot number on the powder and primers. It is no different than any other load out there that is a maximum load for the rifle. Anytime that something changes in a load it needs to be worked back up.

I have a load for my .340 Weatherby shooting 225 grain Barnes TTSX at 3,000 fps. You can't even find that load in the newer Barnes manuals, every thing is a lower speed. But I found it safe in my rifle and it was below what the maximum load was for the powder that I was using.

There will be someone along that has access to load data where they can put in your information and see what comes up.

 

[Ridge Runner]

Ask your custom gun and ammo maker about the pressures and load data to replicate your custom loads to verify the information you have.

The other guy you asked to duplicate your custom load could be referring parroting information from 1 or 2 different reloading manuals and not taking into account which reloading ammo manufacturer has the best attorneys. As in there is the possibility that manufacturer's load data for legal reasons is reduced by 10% or more to keep loads within safe pressure range in case someone wants to produce max charge reloads.

PS 375 Ruger Fan's following thread pretty much defines my point.

 

[375 Ruger Fan]

I use 67.5 grs of H4350 and get very accurate loads at 2700 fps with 225 gr Swift A Frames. The Swift manual says I should get 2749 fps. I don't care about the 49 fps difference, I have a SD of 2.6 and ES of 6. Yes, that's from only a 4 shot group, but SAFs are hard to come by and expensive.

The Swift manual shows 67.0 grs of IMR-4350 as a max load, 90% load density and yields 2715 fps.

The highest velocity load listed in the Swift book is 76.5 grs of RL-25, 102% load density (compressed load) and yields 2815 fps.

 

[AimSmall]

Swift book max load IMR4350 w/225 aframe is 67gr = 2,700fps

Quickload shows 61,744psi w/225 Swift Aframe over 70.5gr IMR 4350 = about 2,781fps

2,900 sounds fast. Have you chrono'd that load?

 

[Scott CWO]

Swift book max load IMR4350 w/225 aframe is 67gr = 2,700fps

Quickload shows 61,744psi w/225 Swift Aframe over 70.5gr IMR 4350 = about 2,781fps

2,900 sounds fast. Have you chrono'd that load?

Okay so according to Quickload, the load is not over SAAMI of 64,000 psi. That is good to know. Is Quickload pretty reliable?

The builder says he chrono'd it but years ago. He sent the info and scope to Premier Reticles for the dots with 2900 listed but that does seem high for the fps.

 

[AimSmall]

Start low, watch for pressure - the number one rule.

 

[JimP]

I'd say that you need to get them on a chronograph and see just what the velocity is, then go from there.

I'm not saying that what he told you but with a custom rifle things can vary.

 

[Frederik]

There is not enough info to safely help you with a load.

Firstly what is your barrel length ???
Case volume after being fired
Total overall length of the cartridge
Did you ever measure the speed of the rounds before?

Quick Load is dependable if you input all correct info best way to check for pressure is to measure the speed. Flatened primers if all is in good order is a sign that you have already gone over pressure as an example measuring speed with a decent chrony helps you to stop before the maximum speed is reached.

 

[Scott CWO]

There is not enough info to safely help you with a load.

Firstly what is your barrel length ???
Case volume after being fired
Total overall length of the cartridge
Did you ever measure the speed of the rounds before?

Quick Load is dependable if you input all correct info best way to check for pressure is to measure the speed. Flatened primers if all is in good order is a sign that you have already gone over pressure as an example measuring speed with a decent chrony helps you to stop before the maximum speed is reached.

24" barrel
Will only use unfired brass
OAL is 3.30
I didn't but gunsmith said 2900

 

[Altitude sickness]

Scott,
Call Hendershots and ask if they will build a test load according to what info you have. Or a load ladder built by them.

And see how it shoots.

 

[hoytcanon]

Hodgdon lists their max iMR 4350 load at 72.0 grains compressed with a 225 SP @ 2832 fps and 52,000 CUP which is just over 62K psi... I would say the load is safe to use in your rifle, but to be "safer" work up to it. If you get to within 50 fps of the original load your holdovers will be close enough out to 500 yards. I will run a table and check that.

 

[hoytcanon]

Here are some trajectory tables for your original load and for the loads from Hodgdon data using their 72.0 grain compressed load. The difference in trajectory is only 2" @ 500 yards, when comparing your stated 2900 fps vs their 2832 fps... if your builders velocities were on the high side, there may be no difference... different lots of powders on account for this much variance. Testing will prove out the holdovers. The colored chart is the MPBR with a 4" KZ radius, the black and white charts compare the two loads (2832 & 2900 fps) when using a 200 yard zero.

 

[hoytcanon]

Both Hodgdon and Nosler list the 225 Accubond at 2880+ fps, Hodgdon with 76.0 grains of Hunter and Nosler with 71.5 grains of IMR 4350. You might want to try some loads with the 225 Accubonds and see how it aligns with the holdovers on your scope. I assume that your scope has a fixed power and is not an adjustable zoom scope? If it is adjustable, that fixes your problem right there... you simply find the power setting that aligns with your holdovers for whatever load you are shooting.

 

[Frederik]

Looking at QL it seems 2900fps would be quite a bit into the red with the data you gave me.
70.2 gr IMR4350 with the average Case volume would come out to 2784fps.

I know Quickload is conservative most of the times but 2900fps is quite a jump from 2800fps and at 70.2gr your case is already full 100.3%

N550 with 69.8gr of powder gives you a max of 2830fps and 97.6% case filling.

 

[hoytcanon]

Two loads @ 2900 & 2832 fps, temperature and elevation corrected... utilizing a 200 yard zero, differential is the same = +/- 2" @ 500 yards.

 

[Rare Breed]

Okay so according to Quickload, the load is not over SAAMI of 64,000 psi. That is good to know. Is Quickload pretty reliable?

The builder says he chrono'd it but years ago. He sent the info and scope to Premier Reticles for the dots with 2900 listed but that does seem high for the fps.

I use QL as well. It is built to be conservative (I have spoken to the lady who coded it). This means there is a built in safety factor so as long as you have entered everything correctly the PSI will be slightly overstated which should make you feel better

 

[shootist~]

The first thing I would do is get an Accurate chronograph reading. Find someone with a LabRadar, Garmin, or Magnetospeed V3 that knows what they are doing. As few as three shots should work.

Take a box of factory along too, and get a reading from them first - as a way to set up the chronograph and conserve your custom loads. And who knows, factory ammo might just be the best option. You can always test the scope at known distances and adjust as needed.

Also, if that person is an experienced reloader, get them to inspect your fired brass for any pressure signs.

Second, I would have someone with the proper gear pull a bullet (or two) and get an actual powder weight. Take nothing for granted when someone other than yourself loaded the ammo.

 

[shootist~]

FWIW - way back when I bought my Sako A-IV 338 WM, I tested 225 gr Hornadys, using IMR-4350. I can't locate my old loading data, but *from memory*, I hit an accuracy node at ~2,800 fps. (*IIRC* that was at 70.0 grains of IMR4350.)

However, when shooting these in summer temps, I saw pressure signs and set them aside. I finally pulled bullets and dumped powder before we moved last year.

My favorite load for that rifle was factory Federal 225 gr TBBCs which are scarce as hens teeth these days.

 

[Mike Van Horn]

If you still have some loads , pull the bullet and weigh the powder
Lyman lists 74 gr max, 225 bullet
Hornady lists 72.8 max

l have owned 4 different 338’s. My loads were all between 66 and 69 grains. Different for each rifle. All with 225 grain bullets. Either a 225 Hornady or a Barnes