WARNING

The load data contained on this site is intended for use with specific rifles and components. Other manufacturers’ equipment will not produce equivalent pressures or velocities. Data contained herein is therefore for the purpose of comparing loads and results against the Reach-ban benchmark grades only, and are not intended for use by individuals – even those who are familiar with correct and safe handloading practices and procedures.

Target Shooter has not set out to produce reloading data but rather to offer alternatives to powders now unavailable due to REACH controls and it is up to the reader to interpret this data to suit his or her requirements and thus no responsibility is assumed in the use of this data. The information is to be used at the sole discretion of the user and the user assumes all risk.

Hodgdon H4895 and VarGet Alternatives Part 3

Let’s look at H4895 alternatives, of which I found eight tubular / extruded examples (Fig. 1). However, by the time I finished testing them, half had already been lost to us. So, we need yet another UK powder availability update. Of those four potential H4895 alternatives we’ve lost in the last couple of years, two are Norma grades whose departure had already been reported (201 and 202). One is from Vihtavuori (N530), and the final disappearing act is IMR-4166. Viht discontinued three grades late last year: N32c ‘Tin Star’ and N105 alongside N530. Nammo Vihtavuori tells us the trio were poor sellers, but more importantly lack linkage to the company’s main products, thus require additional set-up and production resources for the occasional run. With Viht under enormous pressure to increase production levels (doubled over the last 18 months, but the company still can’t meet demand), continued listing couldn’t be justified. IMR-4166’s loss is more surprising given that it is a fairly recent introduction, but Hodgdon explains its contracted manufacturer, General Dynamics Valleyfield in Canada, has been unable to deliver product reliably. This applies to the entire double-based IMR ‘Enduron’ range – 4166, 4451, 4955, 7977, and 8133 – so in total, the number of Reach-compliant powders has dropped by another eight. Better news is that Winchester StaBALL 6.5 has been joined by two other Reach-compliant ‘StaBALL’ grades: StaBALL Match and StaBALL HD, the former a potential VarGet alternative; ‘HD’ a very slow-burning Magnum grade equivalent to Hodgdon Retumbo. 6.5 is with us already and I’ll test it against H4350 later this year. The other two are expected to arrive around now (spring 2023) according to Edgar Brothers, the UK importer. They are pricey grades with recommended retail prices of £65 per pound (454g) for 6.5 and £70 for the others – that’s £154 per Kg.

The Venerable H4895

Like H4350, No. 4895 goes back a long way having been developed by Dupont as an ‘IMR’ grade in the late 1930s specifically for the then new US M2 .30-06 military ball cartridge. It was a key product for Brewster (‘Bruce’) E. Hodgdon when he set up his infant surplus powder business in late 1947, his very first purchase being 20 US tons of US government owned IMR-4895 packed in 150lb drums for $2,000 (50,000lb at 4-cents per pound) and resold in smaller amounts, initially in stiff brown paper bags. Dupont itself didn’t sell this powder grade to handloaders until 1962, whilst WW2 manufacture surplus lots sold by Hodgdon lasted until the 1970s when production of a substitute was contracted to our own ICI Nobel Division in southwest Scotland. So, now there were ‘H’ and IMR versions of the powder, a situation which has continued to the present day. ICI-Nobel closed in the early 1990s, but Hodgdon fortunately found another manufacturing source in the Australian government plant in Mulwala, New South Wales for H4895 and its other extruded grades. With privatisation on the way, Mulwala had become part of ADI, the Australian Defence Industries group alongside the Footscray ammunition plant and Lithgow Small Arms Factory and was eventually purchased by its current owner, engineering multinational Thales.

One presumes that each version of H4895 was somewhat different from its predecessors, but the Mulwala initiative produced a step-change in Hodgdon brand extruded products. Australia was determined to build a significant independent military presence in the light of growing regional threats, also to improve national security by retaining and modernising its ageing defence industries, exploiting their export earning opportunities too. ADI played a central role and in the face of fierce political and environmentalist opposition, the government decided to keep the run-down, obsolete, and polluting Mulwala plant open, further to contribute financially to the private sector rebuilding it. The Hodgdon contract had to be a critical component in these moves, and moreover ADI managers proved to be forward thinking and innovative using R&D work to make step-changes in their products, also proving willing to help Hodgdon Powder exploit customers’ desires and needs for new and improved powders. The first fruit was ADI AR2208, launched to handloaders as Hodgdon VarGet in the US and Europe in 1996. It was and still is, an outstanding mid-range performer and very flexible number suited to many popular cartridges, but of course with its USP – the first really temperature insensitive propellant. Other Mulwala produced grades including H4895 soon followed into what Hodgdon markets as its ‘Extreme Extruded’ range. Another feature of the improved versions was a general move to ‘short-cut’ formulations to improve mechanical powder measure flow and metering. The rest as they say is history, and the main problem has been in making and transporting enough product to meet market demands. Note though that the two 4895s diverged chemically, so that whilst remaining single-based types, they have different burning-rates. Today’s IMR version (made in Canada after the Dupont corporation’s demise) is slower burning, so loads data must not be transposed across the pair.

Today’s H4895

Let’s (literally) look at the current iteration of this 85-year old powder, short-cut and little affected by temperature change. It might be ‘short-cut’ compared to the original Dupont IMR version, but if you look at the photo of it alongside rivals Viht N135 and Norma 202, its kernels are relatively long, albeit of a much more consistent size. It, as with other Hodgdon/ADI ‘Extreme’ grades, lacks the usual near-black graphite colouring. I suspect this is a side effect of ‘Extreme’ technology. ADI and Hodgdon kept the lid on how these powders achieved their resistance to temperature changes for a long time, but it is now generally agreed it involves surface ‘micropores.’ As temperature rises, the kernel expands closing the pores thereby reducing the overall surface area available for the initial charge burn; at low temperatures, kernels contract producing the opposite effect. Presumably graphite coating interferes with the process, and an alternative anti-bridging and anti-static surface treatment has been applied.

Before going onto powders and charges, a reminder of components and rifle chamber details is in order. As with all VarGet/H4895 alternatives, 223 Rem was used with recent purchase Lapua ‘Match’ cases, elderly PMC (Russian) SRM primers, and the 77gn Sierra MK bullet seated well beyond the SAAMI COAL maximum. The chamber throat/leade (often referred to as ‘freebore’) on my rifle are much longer than SAAMI spec allowing a .2.400” COAL (vs SAAMI 2.26”) and through that, increased combustion chamber volume / reduced pressures. The long throat sees maximum charges increase by nearly one grain weight, so the loads used here are well above those in loading manuals and must not be used in a standard 223 Rem rifle / chamber. With the long-freebore chamber and a 30-inch barrel on this F-Class rifle, MVs are also much higher than will be seen in loading manuals or from 223 rifles with 18-22 inch tubes.

Reviewing my test loads, I now consider I pushed the boat out rather far with the benchmark H4895 tests, even taking the long-freebore chamber into account. Hodgdon‘s H4895 maximum for this bullet at the very restrictive and deep-seated 2.26-inch COAL is 22.6gn, albeit compressed and that likely restricting usable charges before pressure did. QuickLOAD (QL) v.3.6. calculated that with my fireformed case water capacity and shallower bullet seating, 24.4gn would produce 3021 fps at 55,241 psi Pmax. Having previously found the program reliable with this powder, I worked up to there, and in the event attained 2,975 fps in the nearly new barrel. (Having rerun QL long after the event with the latest v.3.9., predicted pressures and MVs have risen and 24.0gn would now be my top load were I doing this again.) in any event, there were no over-pressure symptoms, so fortunately the proverbial boat’s hull proved sound, even if the waters underneath were deeper than I feel comfortable with. Later in the year, I fired a long string with this (24.4gn) load past the Labradar to see if several hundred rounds down the barrel had increased pressures and MVs. They had with a new average of 3,021 fps, exactly what QL v.3.6. had originally predicted, and still without apparent pressure signs. So, full barrel run-in had increased MV by around 45 fps (but it was still below the later v.3.9. prediction of 3,058 fps from around 59,000 psi.) The revised benchmark H4895 velocity in this combination is therefore around 2,980 fps on the basis that with hindsight I’d reduce my maximum charge by 0.4gn.

Groups were more variable than with VarGet, but the best were smaller with three out of the eight bracketing 0.2-inches for the four shots. POIs rose across the 3gn charge weight range by a full MOA with only one small two-group plateau showing, and extreme velocity spreads were nothing to shout about at 15 to 42 fps. Note though that Bryan Litz’s work on the effects of a 300-round barrel break-in on the 6 Dasher not only produced a considerable MV rise, but saw matching statistically significant ES reductions. (Modern Advancements in Long Range Shooting Vol. 3 published by Applied Ballistics LLC 2022 using five PRS rifles, four with Bartlein barrels.) Those ES values might therefore have been reduced if the test loads had also been rerun.

Alternatives

The four tubular grades identified in Fig. 1 that are still available to us are covered in this report: Alliant AR-Comp; Lovex S060; Reload Swiss RS40; Vihtavuori N135. They are split equally between single-based types and those incorporating nitroglycerin. The other quartet that are no longer imported or have been discontinued will be the subject of Reach-Out 9, and the three ball types in this burn rate bracket will be range-tested later this year. Although classed as ‘alternatives’, all bar one of this quartet are shown as being ‘quicker’ in burn rate charts, the exception being Viht N135 which is shown as being a tad ‘slower’ on one or two charts, noticeably so on others.

Sticking to alphabetic listing, I’ll kick off with Alliant AR-Comp, a relatively new product to us in the UK and Europe. The US got it earlier being launched there some 12 years ago, and it has proven to be a popular number on that side of the Atlantic. As with all Alliant powders, it is double-based, and this grade is made for Alliant ATK by Eurenco Bofors in Karslkoga, Sweden. It was the first of Alliant’s ‘TZ Technology’ grades challenging Hodgdon/ADI’s supremacy for least temperature affected powders. Originally described as ‘slightly faster’ than Alliant Reloder 15, it is apparent it is at least a full step in that direction, thereby making it nominally close to the benchmark H4895. It has small kernels that flow well and a reasonably high volumetric density making it suited to traditional powder measures and small capacity cartridges giving a near ideal fill-ratio with my maximum charge weight. As the name suggests, it is exceptionally well suited to the .223 Rem cartridge, and across a wide bullet weight range at that. It works well in a large number of other cartridges too including 308 Win. Downsides? It’s expensive and appears to be as easily found as a hen’s tooth right now, even in the USA.

Alliant’s limited 223 Rem loads data don’t include the 77gn SMK, or any others of that weight, surprisingly. The 75gn AMax and 80gn SMK are given maxima of 22.9 and 22.7gn respectively. Sierra’s data for its trio of 77gn models top out at 21.3gn in the very restrictive chamber ‘Bolt-Gun’ tables, and disappointingly there is no AR-Comp listing in the generous-chamber ‘AR-15’ section. QL v.3.6. calculated 23.2gn would produce 2,975 fps at 54,686 psi in my brass and rifle set-up and I chose this as an initial maximum, working up in small steps having no previous experience with this grade. In the event, that charge saw around 2,930 fps, the exact speed unknown with my Labradar’s faulty cable from the power-pack playing up that day. Groups were good throughout with three consecutive incremental charge weights producing small single holes closely bracketing 0.2-inches and ES values were equally impressive for the five batches running almost as low as it gets with this cartridge. Removing the initial ‘fouling shot’ (of five) in group 1 fired from a clean barrel, the six four-round groups averaged under a third inch and remained remarkably consistent in their POIs. All that was lacking was a bit of speed as I’d be looking for around 2,950 fps in this barrel length from the 77gn MK. (I subsequently went up to 23.7gn loading 5-round batches in 0.1gn increments, but groups opened out running at 0.4-0.5gn until the top charge weight of 23.7gn that hit a new node at just over 3,000 fps, but with pressure signs now appearing.) Nevertheless, I see this grade as a ’find’ of this series, and will try it later this year in 6.5mm Grendel, an application for which it is receiving plaudits from American shooters. Despite its name, AR-Comp is not a one-cartridge trick having a wide range of uses including in 308 Win and is very much an H4895 alternative, albeit a rather faster burning one.

Czech Contender

Next up alphabetically, we have single-based Lovex S060 from Explosia a.s. in the Czech Republic. On the face of it, S060 isn’t a contender as it’s markedly ‘quicker’ than H4895 in burn rate charts. It is normally shown as lying between Viht N120 and 130, but Explosia has a serial habit of listing its powders as being faster burning than they turn out in practice. The company’s data have no loads for any bullet heavier than 69gn in the 223 for any of its powders, so no help there. Nevertheless, QL suggested it would still work well with bullet weights in the 75-80gn bracket, and I know that this is an exceptionally flexible and adaptable powder from way back when it was sold here and in the US as Accurate Arms XMR-2015BR. (There is a ’new’ Accurate-2015 on the other side of the Pond, but it isn’t the same thing and is manufactured in Canada, not Europe.) Both versions are normally seen as only suitable for small cartridges (.222 Rem, 223 Rem and suchlike with lighter bullets), or high expansion ratio big-bore jobs such as 45-70 Govt. Nevertheless, QL v.3.6. calculated 23.6gn S060 would push the 77 SMK out at 2,929 fps with 55,308 psi Pmax in my set-up, moreover at an ideal case-fill level, so no compressed loads issues. My marginally lighter top load of 23.5gn was right on the QL prediction with a recorded average of 2,921 fps.

On the target, eight four-round groups averaged 0.33-inch with nothing bigger than 0.45-inch and with 23.3gn producing an outstanding sub-0.2-inch result. Extreme velocity spreads were good ranging from 10 to 28 fps. No velocity / pressure spikes; good results; small kernels; no dramas; good value by today’s prices, so what more could you want? You might answer: ‘a bit higher velocities,’ but with very mild primer pressure signs, I could likely have pushed loads up a little more, even if H4895 speeds will be unattainable. It works very well in 308 Win too with lighter bullets. (165gn and heavier bullets see S060 pressure out at significantly lower MVs than with slower burning grades.) So overall, this propellant is a possible H4895 replacement in selected applications, but its burn speed characteristics limit its usefulness making it less flexible.

Hot Swiss

H4895 alternative number three is Switzerland’s Reload Swiss RS40, manufactured by Nitrochemie Wimmis AG. It is often said that it is the ‘canister’ version of the propellant which Nitrochemie’s part-owner RUAG loads in the GP90 cartridge, the Swiss equivalent of our 5.56mm NATO. Whether that’s so, I can’t confirm, but it would make sense for RS40 to be very close to it, even if it is not identical. It is a very finely grained double-based propellant, or to be more precise, it is what energetics manufacturing people call a ‘high-energy type’, a single-based powder whose kernels are impregnated with nitroglycerin at a late stage in the manufacturing process. (That is, as per Viht N500 series grades, Nitrochemie having sold the know-how to Vihtavuori.) It is also, as with RS52 and RS60/Re17, an ‘EI’ grade with the chemical burn deterrents infused into the kernels and making them more effective than plain surface coating in order to increase MVs within acceptable pressures.

Nitrochemie’s burn rate chart puts RS40 on the same line as H4895, and between Viht N130 and N133. These charts only tell you so much, and are often downright misleading, so we’ll see. Reload Swiss data for 223 Rem include the 77gn Sierra MK – Norma case; RWS SR primer; 2.26” COAL; starting load: 20.2gn; maximum: 23.1gn RS40 for 2,890 fps in a 600mm/23.6-inch test barrel. So, half a grain higher maximum than Hodgdon shows for this combination with H4895, but no compressed-load issues here with this dense fine-grained powder. Half a grain doesn’t sound much, but it’s significant in 223 with ‘heavies’. This RS maximum is shown as producing a hefty 4044 bar peak pressure in a CIP-compliant pressure barrel/chamber, just over 58,650 psi in good old Imperial values.

QL v.3.6. said a slightly lower 22.9gn charge would produce the 55,000 psi I was looking for in my rifle’s set-up, and I adopted the round-figure 23.0gn as my top load. I also started low at 20.9gn which QL calculated at ~44,000 psi (remember the long-freebore chamber and increased COAL reducing pressures in my rifle). Eight batches were loaded using small charge increments, the last couple at 0.2gn. Cold feet, Laurie? Well yeah maybe so! My previous experience of this powder was in small-primer 308 Win F/TR loads with 155gn bullets. Some 10 or so years ago, UK F/TR competitors were seduced by the MVs RS40 can produce with this bullet weight in 308 Win, despite it being rather fast-burning for this cartridge. The then new small primer ‘Palma’ brass was essential in this particular competition application as standard large primer Lapua sees MVs restricted, otherwise case life is only two or three firings. But, get it right in strong SP brass and both MVs and precision can be outstanding. Some 2012 era MVs were so ‘impressive’ in fact that when their unwise users put them up on Facebook and elsewhere online, others muttered about alerting the NRA to what they believed “must surely be dangerous handloading practices in F-Class”!

The F/TR RS40 fad didn’t last long. Heavier bullets, 185gn and above, replaced 155s and the powder pressures out too early with them in the 308 for top performance, but also many users found that their killer 155gn load combination had ‘off-days’. (I also suspect that some of the extreme velocity people found themselves retiring from matches thanks to ‘sudden blown primer syndrome’ without a hint as to what might have changed from previous satisfactory use, small primer ultra-strong brass notwithstanding!) I briefly tried it in 308/155 at what many would have regarded as low MVs for the powder and had some good results, but found it lacked consistency for whatever reason, so went back to cooler, slower burning powders. A legacy of this period is that, as with Viht N540, I treat RS40 warily despite having avoided being ‘burned’. This is almost certainly being grossly unfair to the grade being influenced by others’ loads which with hindsight were abusing the powder.

In this instance with the 223, the 2.1gn charge range saw MVs rise from 2,740 to 2,976 fps, an average rise of just over 11 fps per tenth grain, modest for a ‘fast’ burning high-energy grade. There were no velocity, hence pressure, spikes and primers showed symptoms appropriate to ‘warm’, by no means excessively ‘hot’ loads with my top charges. QL’s v.3.6. MV predictions were very accurate indeed, to within 2 or 3 fps at the top end, and if equally accurate on peak pressure, 23gn would have produced c.55,800 psi in my rifle’s chamber. The program suggests I could have gone a bit higher with 23.5gn producing H4895’s 24.4gn 3,020 fps at around 59,500 psi, higher pressure than the Hodgdon grade likely needed. That would have been an absolutely maximum load even in my long freebore chamber and there is no guarantee that pressure-nasties wouldn’t have appeared out of the blue.

In any event, RS40 matched H4895 performance with my 23gn top load producing MVs just 4 fps short of my revised 24gn H4895’s benchmark 2,980 fps. That it did so with a full grain less powder – a lot for the 223 – suggests that whatever burn rate charts might show, RS40 is the significantly ‘quicker’ one of the pair. (The ‘EI’ technology probably accounts for a fair bit of this fine performance though.) Note too, that I tested RS40 on a cold mid-November day and H4895 on a warm spring afternoon – results might change for the Swiss grade in warm conditions.

Internal ballistics aside, how did RS40 do where it counts, down-range on the paper? Eight four-round groups including the ‘fouler group’ produced an average 0.332-inch group size, within that a range of 0.28 to 0.46” individual groups, very consistent indeed. It might have lacked the 0.2-inchers I was seeking, but these groups were shot in the terrible conditions that I remarked on with Viht N540’s results (Reach Out-7), only they had now worsened with a stiff crosswind having got up and with even lower light levels, so I regard the outcomes as excellent. The POI barely rose over the charge weights and 236 fps range, just gradually moving left. ES values ranged from 9 to 29 fps with all but one string running at 22 fps or less, an excellent result with this cartridge. So, despite my original reservations about RS40, I’ll load up trial batches with higher-BC 80gn match bullets for testing in warmer weather, and if they do as well as these 77gn loads, will carry on with this powder in the 223. In summary though, I must say that while RS40 is a great performer in some applications, its usefulness as an H4895 replacement will be constrained by its ‘quicker’ burn rate, and as with Lovex S060 it is overall a less flexible propellant.

Those Finns Again

I said in Reach-Out 7 that I tested no fewer than six Viht grades in the 223/77, and here’s number five in the form of N135, a single-based extruded grade that’s been around for many years and has a considerable following. Most burning-rate charts or lists show N135 as very close to N140, only a small step ‘quicker’, and in turn the pair as ‘slower’ than H4895, some tables even showing N135 as ‘slower’ than VGT. The German LHS burn rate chart is typical (Figure 2). Yet Viht’s published N135 maximum for the 223/77 is 22.5gn, no less than 2.2gn below N140’s, a vast amount in this cartridge. The resulting MV is also well down. That 22.5gn compares to Hodgdon’s maxima of 22.6gn and 23.7gn for H4895 and VGT respectively, both Hodgdon products given the ‘C’ notation designating compressed loads. (These maximum charges are all in SAAMI-compliant short chamber and COAL form.) So, N135 is slower burning than the two Hodgdons? Apparently not. Interestingly, Viht again increases its maximum for the TMK variant of Sierra 77s, by a full half-grain here despite the amount of charge compression already seen.

If we return to the QL v.3.9. Charge Table (Fig. 1) for 55,000 psi / 105% case-fill loads in my long-freebore set-up, N135 is in a lowly last place ranked by MV and a second look quickly shows why. With its bulk density, my self-imposed 105% case-fill limit is reached before the program calculates it can produce full pressures – 23.2gn producing 50,229 psi Pmax, nearly 5,000 psi down – and that’s with my shallow seated bullet for the long-freebore chamber. (SAAMI and 2.26-inch COAL would be worse, QL calculating the 105% ceiling is reached with 22.0gn, and Viht’s maximum of 22.5gn hitting 107.4% fill. Viht’s tested maximum of 23.0gn for the TMK bullet version is still worse, QL calculating nearly 110% fill, very severely compressed.) That’s on the basis of Lapua case capacity, some US brass would allow more. So, although the Viht data don’t show charges as being compressed, they quite obviously are, and heavily at that, with these bullet-powder combinations. To find out why that should be so, let’s look at Viht’s published data for N100 series powders on its website. N135 is given a nominal bulk density of 870 grams weight per litre volume, low for a short-cut powder, and well below N140’s 910 g/l. The maker’s table conveniently includes specific energy too for its grades and N135 is shown as 3,550 Joules per gram, the second lowest value for any N100 series powder and far below that of our H4895 benchmark whose nominal value is shown in QL as 4,060 J/g (which is considerably higher than that of most double-based/hi-energy grades).

So, we have a relatively bulky and low-energy propellant here – there is far more to this powder performance business than burn-rate alone. That assumes that Viht has got that metric right, and so far the values it has given QL’s compiler have been either accurate or way out on the too-‘slow’ side for those grades tried in this series, pretty evenly divided either way. Which is N135? There is only one way to find out – load and shoot the stuff and see what MVs it produces versus the QL calculations. Before commenting on that, I’ll remind readers yet again of just how valuable / important a long drop-tube powder funnel and the pour method are (yawn!) to pack lower density powders like N135 into the little 223 Rem case, but will forbear to show the pic of my 5.5-inch tube Forster funnel for the umpteenth time.

Also, I reran QL using the much later v.3.9., and got a different result with higher pressures and MVs. The program’s compiler has changed default data values for many Viht powder metrics based on user feedback over the 10 or so years between the two versions. Figure 3 gives a revised incremental load table for N135 in the 223 tuned to my chamber and case capacity with actual MVs from the Labradar shown in red. My maximum charge of 24.0gn was now expected to produce 2,954 fps at 55,814 psi, but actually saw 3,013, some 59 fps higher. Looking down the QL print-out for an equivalent predicted MV, we find 24.6gn is calculated to produce 3,012 fps at 60,582 psi PMax – and that’s the likely pressure my top load produced. On this basis, 23.5gn producing 2,953 fps (estimated 55,800 psi peak pressure) would be a sensible top load in my rifle. That compares to the revised 24gn maximum for H4895 arrived at earlier, so whatever burn-rate charts show, N135 acts as if it is ‘quicker’ in this application but produces lower MVs thanks to its modest energy content. 23.5gn N135 in my rifle’s chamber is roughly equivalent to 22.5-22.7gn in a standard SAAMI chamber and 2.26-inch COAL assuming charge compression isn’t excessive, so the Viht 22.5gn Maximum is exactly that in an industry-compliant chamber and cartridge length, but how the company got an extra half-grain into the case under the TMK bullet variant defeats me, and I’d have to wonder about its pressures too!

How did the powder perform on the paper then? It did well if not outstandingly, would be my verdict taking groups, the charge compression issue, and modest MVs together. The first fouling group had five shots and if the first shot fired from the clean barrel is discounted, we have a 0.34” four-shot group. The resulting six four-shot groups averaged 0.36-inch which although not to be sneezed at, is the largest average of the four grades covered in this report. It is 23.2gn’s 0.53” that pushes the overall average up alongside the absence of any quarter-inchers, never mind 0.2” results. POI remained very stable throughout and ES values were excellent with only one quartet exceeding 20 fps.

The high fill-ratio values are the main downside of this powder, in small cased cartridges anyway. Taking 23.5gn / 2,953 fps as the top load I would likely adopt pressure-wise, this charge is calculated to produce 106% fill. Using the Forster powder funnel and a very slow (dribbled), angled pour reduces that to an inconsequential level of actual compression, but slows the loading process down considerably. N135 is odd man out in this quartet where the other three produced full pressures and acceptable MVs with fill-ratios between 90 and 100%. To see how Vihtavuori got here, we can explore its background, and discover that it was originally developed for a particular application – standard 7.62mm NATO ball ammunition. In other words, a lowish internal capacity variant of the 308 Win case loaded with a nominally 147gn FMJBT bullet to produce 2,800 fps MV from a 21-22” barrel and meet NATO technical specifications for chamber and gas-port pressures, the former set at 415 MPa / 60,191 psi maximum. No doubt, its low bulk density / high fill-ratio works out well in this combination, and having just acquired a 308 Win ‘knockabout’ range-rifle, this is a powder I’ll try soon with the Berger 150gn flat-base match bullet. However, even in the much larger 308 Win case, compressed charges would appear to be an N135 fact of life with many loads.

Reach-Out 9 will report on IMR-4166, Norma 201 / 202, and Viht N530.