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wheelman
October 8th, 2014, 08:29 PM
So I have all of the stuffs that I need to start making up 300BLK rounds. I currently have 245 grain coated lead bullets from Missouri, a 230 grain Lee mold, 130 grain bullets from JD, and 115 grain coated lead bullets from Missouri. I also picked up some factory Remington 220 grain OT FB.

I am planning to stick with H110 for now.

My question is, assuming I stick with published loads, how much variation can I expect between these different bullet weights with associated loads.

IE - do I need to re-sight for each load? I am thinking of sighting in at 100 yds.

This did not really occur to me until just now. Usually, with rifles, I sight for a given bullet and load and then just stick with that.

This is a horse of a different color (to quote the man behind the curtain).

thoughts? suggestions?

I have the AR from the Rumbler auction and a new AAC Handi that I picked up on clearance from Grab-a-Gun so theoretically, I could have each gun sighted for a different load for a different purpose but I am wondering if I have any more flexibility than that.

Thanks in advance for sharing.

Rumbler
October 8th, 2014, 09:15 PM
It has been my personal experience that with my 16" converted AR the supersonic vs subsonic loads make the most difference. What I mean by "most" is the genuine need to resight the rifle. I've pushed . . for instance . . . 150gr bullets subsonic and supersonic. The difference in point of impact was significantly greater doing that than shooting 150gr bullets (at the same speed) at 100 and 200.

I know that is not exactly what you asked, but dang. Here, this will probably serve way better than any words I can cobble together (because there are soooooo many potential variables):

https://www.google.com/search?q=300blk+balistic+table&safe=off&rlz=1C1TSNF_enUS423US423&biw=1366&bih=653&tbm=isch&imgil=PrvanDOSdyGhlM%253A%253BtL9l2WY3Krac5M%253Bh ttp%25253A%25252F%25252Fwww.ar15.com%25252Farchive %25252Ftopic.html%25253Fb%2525253D3%25252526f%2525 253D121%25252526t%2525253D587291&source=iu&pf=m&fir=PrvanDOSdyGhlM%253A%252CtL9l2WY3Krac5M%252C_&usg=__X8nB3UXPjmVdJZMz9DO2xfVyd-Q%3D&ved=0CCsQyjc&ei=4uA1VNiEEMSTyATUhoCoCg#imgdii=_

talon2
October 8th, 2014, 09:35 PM
Think of the light supersonic loads as a regular rifle round, out to about 200 yards they don't act much differently that a .308 winchester. Think of the subsonic rounds like a pistol caliber carbine in terms of performance, except for the much better ballistic coefficient of the rifle bullet, that's what it is. The trajectory chart looks a lot like that big arch out in St. Louis. The long heavy bullets retains energy and velocity very well, but it didn't start out with much either. Unless you are putting a suppressor on it, the light fast loads are the way to go, but the subsonic stuff is fun to play with and really quiet even without a can.