Supersonic Whisper loads in your AR? Lend some advice!

[abyssdncr]

Hey folks,

I wanted to start a thread here to discuss whisper loads for your AR's.

I've got a M1S 16" and am finding some discrepancies in posted load data and real world results. Specifically, I'm developing my deer hunting load for 125 gr. BT.

I'm forming brass from Win. .223 Rem on Hornady dies and using H110 powder. SSK's site seems to be showing loads of 20.5 gr to 22 gr, but they're listing necked up .221 FB brass. I've seen similar data for the .223 brass as well though (I think it was on Feisty Rooster's page). Using Win. small rifle primers, I'm observing over pressure signs at 19 gr of H110 and nasty the-primer-has-become-one-with-the-brass signs at 19.5 gr. (Coincidentally, 19.5 gr. load with the 125 Nosler BT absolutely shredded a spike buck last week-double lung and heart shot. Didn't make it 10 ft.! :D ) 18.5 gr H110 + Win. .223 brass + Win. primers look good with both 125 gr. BT and 130 gr. Sierra SP.

I was reading elsewhere that the Rem primers are more durable and that's what most load data is listing as the primer, Rem 7 1/2. I don't have my chrony yet, (Merry Christmas to me!) so I don't know what velocities I'm getting with these loads. However, it's imperative for me to be able to get at least 2300 fps to maintain the necessary velocity for optimal expansion on the ballistic tip out to 300 yds.

That said, I'm not a huge fan of the H110. Would someone be kind enough to share their experiences with H4227?

I'd appreciate some feedback from other whisper owners...

Thanks,
8)

[jripper]

I have a Model 1 Sales upper also. I have been working with W296 (which very similar to H110) and remington 125 PSP, and have had a similar experience. 19.0 g behind the 125 remingtons showed high pressure, and with 19.5 gr, it will blow primers out of the cases!!!. I am using Federal small rifle primers. 18.5 grains works well, seems to be a safe load in my gun, and is just breaking 2200 fps.

There are so many variables, don't get too hung up on published ballistics/loads. I think you should be able to get 2200 + FPS out of your gun, and I really don't believe that that 100 fps is going to make a lot of difference in the field.

You can try switching primers, but reduce the loads first, and work back up to it, as it could actually increase the pressure.

I have not tried any other powders for supersonics yet, but do have some AA 1680 in my cabinet, and may try some loads with that powder. I'll let you know.

[abyssdncr]

Excellent, I'm happy to hear a little afirmation of my findings. It always feels weird trying a new load for this gun, because you're basically making it up as you go... I pulled all the rest of my 19.5 gr. loads and saved the BT's til I get a decent load figured out. I've been meaning to snag a few hundred of the Remington 125 sp for some cheap load development, but haven't got around to it yet.

This weekend though, at the last gun show, I broke down and bought a lb. of H4227 and a couple hundred 147 Winchester FMJs to plink with. I basically copied load data for the 146 gr. .357 Mag. I got four sets of 10 loaded up at 14.5, 15.0, 15.5, & 16.0 grains of H4227. Weather got too nasty to shoot on Sunday, and then I got a crazy hair up my rear that's got me stripping my upper apart and sending the barrel off for some gunsmithing. I guess I'll see how they shoot in a couple weeks. Gotta say though, I do like working with the extruded powders much more than the H110. My case of Rem 7 1/2 primers should be waiting at the shop for me now. Guess we'll see if that makes any difference either.

Thanks,
Brian

[pg55]

I used 150 grs with with 18 grs of H110 behind it with good results.This month I want to try some 125grs loads so I guess I will load 2 rounds at 18.5 adding .5 grains to 20.5. I will stop at pressure indication on primers. I always use Rem 7.5 primers. Are you checking out your scales with calibration weights?

[40mmpumpgun]

Email Nick... vwguy@zoominternet.net He's really got it down real well with the whispers guns, reloading and cycling problems and cures. Just mention that Brian turned you on to him. I forgot to mention that he builds them also....