Yay, my FGMM clone worked!

LoneWolfUSMC

LoneWolfUSMC

Lt. Colonel
Full Member
Minuteman
Jan 9, 2008
7,377
17
Southern Indiana
www.8541tactical.com
#1
I am pretty stoked. I just got back from the range and shot my handloads back to back with my duty ammo (168gr Gold Metal Match) with the same zero.

Shooting two different zero's is a pain. While my preferred load is hotter and more accurate I will give up a little bit of accuracy for the convenience.

For those who are wondering the clone ended up as the following:

168gr SMK (#2200)
42.5gr Reloder 15
CCI200 Primers
Federal Brass (once fired from FGMM and FL resized)

In the 90+ degree heat we had today it worked as intended. I will have to see if the long range trajectory ends up being the same and if the temperature variance is close enough, but it looks promising so far.

To test it, I first shot five shot groups one after the other. Then to get as close a comparison as possible I fired four more five shot groups "round robin" style where I would fire one handload, then one FGMM so that the barrel stayed the same temp and the wind conditions were as close as possible.
 
#5
Re: Yay, my FGMM clone worked!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Captain Kick-Ass</div><div class="ubbcode-body">take that up with LL (Tiny Dancer) </div></div>


the fairy stick may start waving!!!!!!!!!!

Did you buy both those ladders from UKD??? one for LL and one for BK?????



Later
 
#6
Re: Yay, my FGMM clone worked!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">
In the 90+ degree heat we had today it worked as intended. I will have to see if the long range trajectory ends up being the same and if the temperature variance is close enough, but it looks promising so far.

To test it, I first shot five shot groups one after the other. Then to get as close a comparison as possible I fired four more five shot groups "round robin" style where I would fire one handload, then one FGMM so that the barrel stayed the same temp and the wind conditions were as close as possible. </div></div>

I'd try throwing both batches in a cooler with a ice pack and letting it chill... then repeat. If that doesn't work for ya, try IMR4064. it might coorelate better with FGMM through the temp range as a single base powder. I read somewhere of the claim that 4064 was same speed as whatever FGMM uses.
Ive done simular with 4064..I'm a bit surprised you were as high as 42.5gr of RL-15, especially at that temp. I would have guessed at least 0.5gr less. Chamber should be relative since you matched MV. Same seat depth as FGMM?

 
#9
Re: Yay, my FGMM clone worked!

LW-sweet! I think a clone load is very good to use.

42.4 of IMR 4895 in Fed, LC match or Lapua does the trick for my rifle. I use Nosler 168's seated to the same ogive length as FGMM. Avg velocity in different temperatures has been within 5fps of FGMM and the SD is with 1.

I like it as I shoot matches, and keep some FGMM on hand for easy "just in case" ammo.

I'm going to be swithing soon to 175's so I'll have to rework for a 175FGMM clone.
 
#10
Re: Yay, my FGMM clone worked!

For a starter, simply try swapping the bullet. M118 and M852 are both the same load except for the bullet, nominally 42.0gr of IMR-4895. BTW, published arsenal loads are often simply plausible fiction/approximation; actual loads varied by powder lot, and were chosen to match a given velocity standard. M118 was targeted at 2550fps (+/- 30fps @78ft), and so was M852. My Sierra manual maxes the 175/180's at 41.5gr of IMR4895, and the 168 at 42.1Gr of IMR4895.
 
#11
Re: Yay, my FGMM clone worked!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">Barrel length and velocity range (or reasonable estimate)? </div></div>

This is on a 26" factory barrel. I would guess velocity is around 2600 or so, but I don't have a chronogragh. Going to have to shell out for one soon. I keep coming into problems where one would be useful.
 
#13
Re: Yay, my FGMM clone worked!

Before I had the Chrony, the target was my chronograph.

When the chrony was working it offered me all kinds of info, but not a lot of it had any direct correlation to accuracy. It did a good job of providing data to put into my Pejsa spreadsheets so I could plot ballpark estimates of drops and drifts way out there, but again, it only really got me into the ballpark.

When it stopped working I missed it, but life continued anew. What I had learned from it was very useful, but once it was O/O service, there was never any really compelling need to get it fixed. Most of what I had learned related to a good gut feel for loads and drops, and a realization the SD/ES info is less useful than I had originally thought. I'd pay it more credence if it could be better correlated to accuracy expectations/realizations.

Greg
 
#14
Re: Yay, my FGMM clone worked!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">They were seated to the same COL as FGMM. I went with RL15 initially because that's what I have on hand. If it doesn't work I will give the 4064 a try (if I can find it anywhere). </div></div>

I probably got a bit lying around I could part with. I could bring the chrono down with me if ya needed it. Let me know.
cool.gif
 
#15
Re: Yay, my FGMM clone worked!

Sobr,

I shoot 175's SMK's out of my .308 with Lapua brass, and my velocities are pretty close to FGMM. I load 44.3 grains(I will double check this when I get home this evening) of IMR 4895 with CCI BR2 primers. OAL of the cartrige is 2.82 inches. I chrony'd the ammo an got an average of about 2675 fps. With a little more work I imagine you could get it pretty darn close to FGMM.
 
#19
Re: Yay, my FGMM clone worked!

i'm working on my first handloads...started out w/ 2# of varget and 2 of imr4895...
started w/ the varget came up w/ 41 gr for a 175smk, and 42 for the 168, really tight groups but wanted to try for a higher node, ended up w/ 44gr 175 and 46 for the 168s, shooting about a half moa right there.
Havent cracked open the imr4895 yet, but i still have some brass to play around with.

the above was for a stock rem700 26" 12 twist
 
#22
Re: Yay, my FGMM clone worked!

my 168gmm clone load is as follows:

168gr smk
fgmm brass f/l sized
42.0 gr varget
fed primer

shot them side by side with the gmm out to 500 and my zero's were on... i was stoked...
 
#23
Re: Yay, my FGMM clone worked!

Interestingly is seems that the last time I went out the POI of my "copy" was about 2" high vs. the 168 FGMM. This was at about 80*F. It's interesting that I am seeing a difference at lower ambient temp, but not at higher temps.

I may have to back it down .5gr and try again.

The advantage is that every time I go to the range I shoot 1 cold bore shot and 1 followup shot with FGMM before I run whatever else I am doing. This way I can start to track the variation of the "clones" versus the real deal.

Of course as soon as I get all this data we will probably switch to 168 TAP and I will have to do it all over with the A-MAX bullet.
 
You must log in or register to reply here.

Similar threads

1
Which Charge weight should I use?
Replies
5
Views
336
straightshooter1
straightshooter1
N
First Timer Help! LR Hunting 308 Handloads
Replies
44
Views
936
JerkyFreak
JerkyFreak
9
Load testing questions
Replies
40
Views
526
502Chevelle
5
P
Lost about 90 fps - 300WM once fired brass
Replies
12
Views
390
penguinofsleep
P
R
What the heck is going on here?
Replies
21
Views
983
Rider47
R
Top Bottom
Back
Home
Forums
Merch
Alerts