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IMR4166 loads for .223?
- Thread starter Gbetz
- Start date
It shoots amazing in several of my rifles.Yes. With the Varget shortage I found IMR 4166 and got it. Will not go back to Varget in 223.
According to hodgdon's site, 23 gr is max. Check bullet and powder maker sites. plenty of data. Plenty of manuals too
There isn't for 4166 and the 223. Nobody other than Hodgdon provides it despite it looking a match made in heaven if you believe burn-rate charts. (I don't!) There is however plenty of data in recent manuals for this powder and larger cased cartridges up to around 30-06 size.
For a powder that's been around for several years now, I found this both strange and its absence in 223 also made me very wary. Trying it in a long-throat (between Wylde and PT&G ISSF) 223 with the 77gn Sierra MK, I found that it a) goes into compressed territory at a lower charge than I expected or liked; b) started to produce pressure signs at considerably below VarGet max charges and at lower MVs. A top charge that was happily used with H4895 was too high and also gave lower MVs. This ties in with the powder review in Handloader magazine, and its author says another independent test he'd read gave same results
So, it's a suitable 223 Rem alternative in the sense that it can be used in the cartridge with this bullet weight, but is far from being an optimum choice.
I am looking for load data using the above mentioned powder using Berger 75g VLD’s. Is anyone using this combo? Thanks
There is 223 and 223 amongst users on this forum with 12-twist factory rifles and SAAMI spec 0.025" freebores up to 7 twist or faster competition rifles with 200 thou' plus freebores. What are you loading for? Likewise brass make - a vital factor with this little cartridge given a huge range of case makes, sources, and internal capacities.
You will need to work up your own load for your gun. Use hodgdons data for that. But 4166 should be excellent in 223.
It shot awesome in my 257AI, 284, and 7x7AI. In my testing of 4166, 4451 and 4955, they all hit peak pressure suddenly and produced best accuracy at or very close to max. They also prevent copper build up in my rifles. After 50 rounds of Hammer bullets, my borescope show only a haze of copper, very light and hard to see.
You will need to work up your own load for your gun. Use hodgdons data for that. But 4166 should be excellent in 223.
The study you quote isn't a range-tested comparison as it concentrates on temperature sensitivity. The author says of IMR-4166:
IMR 4166: This newer propellant produced by General Dynamics in Canada had the best temperature insensitivity and may be the best substitute for Varget across a wide temperature range with 77 to 80 grain bullets. In another study, IMR 4166 was identified as the best replacement for Varget between 61°F and 103°F for .308 F-TR rifles. (see note 1).
Note use of 'may be the best substitute' and that based on results from 308 Win range-testing. As I said in my earlier post, there is plenty of data printed for larger case cartridges with 4166 in recent manuals, especially 308 Win. Hodgdon aside, there is none for 223 Rem. With a nominal burn-rate between H4895 and VarGet, it should be ideal. There are many examples around of powders that should be ideal, but in real life loads, simply aren't. If 4166 were anything like 'ideal' for this application, even workmanlike, I'm sure there would be plenty of independent data for it.
I’m loading 22.8 behind a 69 SMK and getting 2786fps out a 25 inch barrel, so not to fast but I like it.
The study is temp response focused but its shows several other notes as well.The study you quote isn't a range-tested comparison as it concentrates on temperature sensitivity. The author says of IMR-4166:
IMR 4166: This newer propellant produced by General Dynamics in Canada had the best temperature insensitivity and may be the best substitute for Varget across a wide temperature range with 77 to 80 grain bullets. In another study, IMR 4166 was identified as the best replacement for Varget between 61°F and 103°F for .308 F-TR rifles. (see note 1).
Note use of 'may be the best substitute' and that based on results from 308 Win range-testing. As I said in my earlier post, there is plenty of data printed for larger case cartridges with 4166 in recent manuals, especially 308 Win. Hodgdon aside, there is none for 223 Rem. With a nominal burn-rate between H4895 and VarGet, it should be ideal. There are many examples around of powders that should be ideal, but in real life loads, simply aren't. If 4166 were anything like 'ideal' for this application, even workmanlike, I'm sure there would be plenty of independent data for it.
First and foremost 4166 is excellent in its temperature response in 223. Second it does achieve high velocities with 77 grain bullets, 2750+ was achieved. And lastly it achieved comparable accuracy to varget by simply matching velocity to his competition load, not doing a full load workup. .7 moa at 200 yards vs .66 moa for varget. The few other reports I have seen were generally very positive.
I don't know why we don't see more reports on this powder for heavies in 223 but all the ones I did find said it worked well.
Ned Ludd
Silver $$ Contributor
One big problem pushing heavies in a .223 Rem is brass life. It's typically very poor. I tried IMR 4166 in the .223 Rem under 90 VLDs in one of my F-TR rifles when it first came out. The results with IMR 4166 in my hands were obviously not nearly as good as H4895, and so I didn't pursue it any further. The IMR 4166 generated markedly less velocity than H4895, the kernels were nearly twice as large, which is not the direction to go with the small .223 Rem case, and even at lesser velocity, the pressure was as high or higher than with H4895. If I were looking for a substitute powder for .223 Rem with better availability in these times of reloading component shortage, I might look beyond IMR 4166. I haven't ever tried CFE223 or AR Comp, but they might be better possible alternatives if the kernels are relatively small. I have tried N140, and it also suffered from generating higher operating pressure for a given velocity as compared to H4895. Nonetheless, any of these alternatives; i.e. N140, CFE223, AR Comp, or even IMR 4166, might represent reasonable substitute powders for .223 Rem if the alternative is not shooting because you ran out of H4895 or Varget and can't find any more. Certainly, I wouldn't necessarily rule any one of them out until I had actually bought a pound and tried it out.
A drop tube is your friend with IMR Enduron 4166
The Forster Universal funnel with a small-bore 5.5-inch tube was used in my case with a very slow swirl pour. Charge compression would have occurred significantly earlier without this. Recent manufacture Lapua brass was used with 30.5gn water capacity fireformed. Winchester or LC would have given a bit more latitude.
The IMR 4166 generated markedly less velocity than H4895, the kernels were nearly twice as large, which is not the direction to go with the small .223 Rem case, and even at lesser velocity, the pressure was as high or higher than with H4895.
My findings too with the 77gn SMK. This is one part of a triple mega-test series to identify alternatives to H4895/VarGet; H4350/414; 4831 which, alongside 20+ others from Hodgdon and IMR, we have lost on our side of the Atlantic to the 2020 environmental / health & Safety REACH regulations. I did H4350 / H414 first in 7mm-08; H4895/VGT in 223 Rem underway now; finally H4831sc in 284 Win to finish off.
In all, I've identified 27powders, 18 tubular and 9 ball as H4895/VGT possible alternatives. Four tubulars (three Reload Swiss and Lovex SO60 which used to be Accurate-2015 in the US until 2006) are Europe-only products as is one ball type from Eurenco P.B. Clermont. (Ramshot Wild Boar, sold as Accurate-2520 for a while to you, but this grade is apparently now sourced from General Dynamics St. Marks.) 15 extruded grades + the two benchmark H4895/VGT series have been fired so far mostly in four round batches, but a few in 5s. Listed burn rates vary from Norma 201 / Viht N530 / Lovex SO60 to Re15/N203-B and Viht N540/150/550.
Returning to IMR-4166, my highest charge of H4895 gave 2,975 fps to the 77 (30-inch barrel), no significant pressure signs. I will however redo my top benchmark loads as they were fired in a Benchmark barrel with only 100 or so rounds down it. I wouldn't be surprised to obtain higher MVs and pressures now due to further barrel run-in.
Because of my concerns over 4166, I started very low and my initial top charge, which taking the longer FB chamber and COAL into account, was about equivalent to max Hodgdon with the 77 in a SAAMI 223 Rem chamber, only produced 2,800 fps. So I carried out a follow-up session of six by 5-rounds rising in 0.2gn steps to finally match my H4895 top charge.
This charge produced 2,947 fps - ie some 50 fps down on the same weight of H4895 as it was in the near-new barrel. However, unlike H4895's same weight charge, there were now significant pressure signs. If I were considering using this powder in 77s/80s, I'd reduce charges by 0.4gn. That weight gave 2,902 fps nearly 75 down on H4895.
MVs / bulk aside, the rest of 4166 was good. The second session of six batches fired produced an average group size of 0.29" C to C at 100 yards fired off the bench in a full-spec F-Class rifle (5-shot groups) despite poor conditions on the day. Some, though not all ES values were good to superb. This ties in exactly with what R H Vanderberger Jnr wrote in Handloader magazine about 4166's performance - poor MVs (he stated specifically he never came close to matching Hodgdon's claims over four or five cartridges); good groups; low ES. He said that this also mirrored the findings exactly by an unnamed second American writer who did a thorough multi-calibre test for another publication.
(The reports on 4350 alternatives range-tests can be found here -
http://www.targetshooter.co.uk/?p=3609
http://www.targetshooter.co.uk/?p=3624
http://www.targetshooter.co.uk/?p=3657
http://www.targetshooter.co.uk/?p=3683 )
I'm just starting to write the introduction to the 223 H4895/VGT tests and will then move onto H. VarGet tubular alternatives in two further sections followed by H4895 alternatives including 4166 as a further two sections shortly thereafter having hopefully finished the final tubular powders range-testing. (We are teetering on the edge of another Covid lockdown starting in January though excactly as per 12 months ago. As covered firing points are classed as 'indoor locations', any additional restrictions on person-numbers, distancing etc would cause another full-stop as they did for nearly four months in 2021.
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It is my absolute go-to for year-round 308. 155 Scenar. It's accounted for many groups & hits that to tell of them makes me look like a liar.
I have a married couple pair of friends who shoot FTR at GB National league level. They too have had good results with 4166 in 308 Win with IIRC 185gn Juggernauts. (Might have been 155.5 Bergers tho' as they shoot them in some matches and conditions.) They have returned to Viht N150 though as it is very much cheaper here in the UK and availability is also better.
That was why I was surprised as to why nobody other than Hodgdon lists 4166 in 223 Rem with heavier bullets when I did my initial desk research for this exercise. I now know why though, and I'm sure Sierra and others have tried 4166, but rejected it in this application.
Definitely interested in your next article. Thankyou for sharing.The Forster Universal funnel with a small-bore 5.5-inch tube was used in my case with a very slow swirl pour. Charge compression would have occurred significantly earlier without this. Recent manufacture Lapua brass was used with 30.5gn water capacity fireformed. Winchester or LC would have given a bit more latitude.
My findings too with the 77gn SMK. This is one part of a triple mega-test series to identify alternatives to H4895/VarGet; H4350/414; 4831 which, alongside 20+ others from Hodgdon and IMR, we have lost on our side of the Atlantic to the 2020 environmental / health & Safety REACH regulations. I did H4350 / H414 first in 7mm-08; H4895/VGT in 223 Rem underway now; finally H4831sc in 284 Win to finish off.
In all, I've identified 27powders, 18 tubular and 9 ball as H4895/VGT possible alternatives. Four tubulars (three Reload Swiss and Lovex SO60 which used to be Accurate-2015 in the US until 2006) are Europe-only products as is one ball type from Eurenco P.B. Clermont. (Ramshot Wild Boar, sold as Accurate-2520 for a while to you, but this grade is apparently now sourced from General Dynamics St. Marks.) 15 extruded grades + the two benchmark H4895/VGT series have been fired so far mostly in four round batches, but a few in 5s. Listed burn rates vary from Norma 201 / Viht N530 / Lovex SO60 to Re15/N203-B and Viht N540/150/550.
Returning to IMR-4166, my highest charge of H4895 gave 2,975 fps to the 77 (30-inch barrel), no significant pressure signs. I will however redo my top benchmark loads as they were fired in a Benchmark barrel with only 100 or so rounds down it. I wouldn't be surprised to obtain higher MVs and pressures now due to further barrel run-in.
Because of my concerns over 4166, I started very low and my initial top charge, which taking the longer FB chamber and COAL into account, was about equivalent to max Hodgdon with the 77 in a SAAMI 223 Rem chamber, only produced 2,800 fps. So I carried out a follow-up session of six by 5-rounds rising in 0.2gn steps to finally match my H4895 top charge.
This charge produced 2,947 fps - ie some 50 fps down on the same weight of H4895 as it was in the near-new barrel. However, unlike H4895's same weight charge, there were now significant pressure signs. If I were considering using this powder in 77s/80s, I'd reduce charges by 0.4gn. That weight gave 2,902 fps nearly 75 down on H4895.
MVs / bulk aside, the rest of 4166 was good. The second session of six batches fired produced an average group size of 0.29" C to C at 100 yards fired off the bench in a full-spec F-Class rifle (5-shot groups) despite poor conditions on the day. Some, though not all ES values were good to superb. This ties in exactly with what R H Vanderberger Jnr wrote in Handloader magazine about 4166's performance - poor MVs (he stated specifically he never came close to matching Hodgdon's claims over four or five cartridges); good groups; low ES. He said that this also mirrored the findings exactly by an unnamed second American writer who did a thorough multi-calibre test for another publication.
(The reports on 4350 alternatives range-tests can be found here -
http://www.targetshooter.co.uk/?p=3609
http://www.targetshooter.co.uk/?p=3624
http://www.targetshooter.co.uk/?p=3657
http://www.targetshooter.co.uk/?p=3683 )
I'm just starting to write the introduction to the 223 H4895/VGT tests and will then move onto H. VarGet tubular alternatives in two further sections followed by H4895 alternatives including 4166 as a further two sections shortly thereafter having hopefully finished the final tubular powders range-testing. (We are teetering on the edge of another Covid lockdown starting in January though excactly as per 12 months ago. As covered firing points are classed as 'indoor locations', any additional restrictions on person-numbers, distancing etc would cause another full-stop as they did for nearly four months in 2021.
Thanks for the detailed response. Lots of good info here.The Forster Universal funnel with a small-bore 5.5-inch tube was used in my case with a very slow swirl pour. Charge compression would have occurred significantly earlier without this. Recent manufacture Lapua brass was used with 30.5gn water capacity fireformed. Winchester or LC would have given a bit more latitude.
My findings too with the 77gn SMK. This is one part of a triple mega-test series to identify alternatives to H4895/VarGet; H4350/414; 4831 which, alongside 20+ others from Hodgdon and IMR, we have lost on our side of the Atlantic to the 2020 environmental / health & Safety REACH regulations. I did H4350 / H414 first in 7mm-08; H4895/VGT in 223 Rem underway now; finally H4831sc in 284 Win to finish off.
In all, I've identified 27powders, 18 tubular and 9 ball as H4895/VGT possible alternatives. Four tubulars (three Reload Swiss and Lovex SO60 which used to be Accurate-2015 in the US until 2006) are Europe-only products as is one ball type from Eurenco P.B. Clermont. (Ramshot Wild Boar, sold as Accurate-2520 for a while to you, but this grade is apparently now sourced from General Dynamics St. Marks.) 15 extruded grades + the two benchmark H4895/VGT series have been fired so far mostly in four round batches, but a few in 5s. Listed burn rates vary from Norma 201 / Viht N530 / Lovex SO60 to Re15/N203-B and Viht N540/150/550.
Returning to IMR-4166, my highest charge of H4895 gave 2,975 fps to the 77 (30-inch barrel), no significant pressure signs. I will however redo my top benchmark loads as they were fired in a Benchmark barrel with only 100 or so rounds down it. I wouldn't be surprised to obtain higher MVs and pressures now due to further barrel run-in.
Because of my concerns over 4166, I started very low and my initial top charge, which taking the longer FB chamber and COAL into account, was about equivalent to max Hodgdon with the 77 in a SAAMI 223 Rem chamber, only produced 2,800 fps. So I carried out a follow-up session of six by 5-rounds rising in 0.2gn steps to finally match my H4895 top charge.
This charge produced 2,947 fps - ie some 50 fps down on the same weight of H4895 as it was in the near-new barrel. However, unlike H4895's same weight charge, there were now significant pressure signs. If I were considering using this powder in 77s/80s, I'd reduce charges by 0.4gn. That weight gave 2,902 fps nearly 75 down on H4895.
MVs / bulk aside, the rest of 4166 was good. The second session of six batches fired produced an average group size of 0.29" C to C at 100 yards fired off the bench in a full-spec F-Class rifle (5-shot groups) despite poor conditions on the day. Some, though not all ES values were good to superb. This ties in exactly with what R H Vanderberger Jnr wrote in Handloader magazine about 4166's performance - poor MVs (he stated specifically he never came close to matching Hodgdon's claims over four or five cartridges); good groups; low ES. He said that this also mirrored the findings exactly by an unnamed second American writer who did a thorough multi-calibre test for another publication.
(The reports on 4350 alternatives range-tests can be found here -
http://www.targetshooter.co.uk/?p=3609
http://www.targetshooter.co.uk/?p=3624
http://www.targetshooter.co.uk/?p=3657
http://www.targetshooter.co.uk/?p=3683 )
I'm just starting to write the introduction to the 223 H4895/VGT tests and will then move onto H. VarGet tubular alternatives in two further sections followed by H4895 alternatives including 4166 as a further two sections shortly thereafter having hopefully finished the final tubular powders range-testing. (We are teetering on the edge of another Covid lockdown starting in January though excactly as per 12 months ago. As covered firing points are classed as 'indoor locations', any additional restrictions on person-numbers, distancing etc would cause another full-stop as they did for nearly four months in 2021.
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