I just came back from the range after shooting my browning 300 win mag a few times. I had worked up some loads using a 180 gr. partition and Rl-22. Max load according to nosler is 75.5 gr. My starting load was 70 gr. I then worked up to the 75.5 gr max working in 1 gr increments. OAL was 3.350" as this was all my magazine would permit. When I shot the loading with 72 gr., I noticed definite signs of high pressure(sticky bolt lift, primers beginning to flatten, etc.), so I stopped there. I realize that each gun is unique and will have its own max load, but I have never experienced signs of high pressure 3.5 gr under listed max. I am trying to rationalize in my mind what could be causing this. I used the same primers as nosler, same cases, etc. I have heard people on the forum talk about how RL-22 is temperature sensitive, but it was only 80 degrees at the time of testing. After reading a post by a fellow member last night about full-length resizing, I am starting to wonder if my resizing practices are at fault. I typically follow the die manufacturers recommendation by allowing the sizer die to bottom out against the shellholder. I've heard a few people say that results in setting the shoulder too far back. If true, looks like that would decrease case capacity and increase pressures with respective loadings. Anybody out there experienced this or have any suggestions as to what I might be doing wrong? Please help.

What is the velocity? The books are just a guide not cut in stone. You may well be at your rifles max.

Don't know what the velocity is. I have not yet invested in a chrono. That is next on my list.

I don't find this unusual at all as the reloader series of powders has long been known for lot to lot variation. It isn't a favorite of mine, but when it works, it works well. Given a lot that burns slow, as RL 22 should, it is one of the best powders for the 300 Win mag.

The problem with RL-22 is not temperature sensitivity but significant variations in the lot-to-lot burning rate. In other words, some lots of RL-22 are notably faster than others.

My guess is that you have one of the faster lots of RL-22, which could very well give you pressure problems as low as 72 grains (and the Nosler manual information came from a slower lot). A fast lot of powder combined with the deeper seating depth necessitated by the somewhat short magazine of your Browning could very easily run high pressures.

While I don't recommend resizing a case any more than is necessary to ensure that it will readily reenter the chamber, squeezing the case down will have negligible effect on chamber pressure. The effective size of the pressure vessel (which is determined by the size of your chamber and rifling leade) has nothing to do with the static size of the very fluid brass case.

Is there another powder that will produce velocities between 3000-3100 fps without the lot to lot variations of RL-22.

I believe you would be well served by the following:
V-V N165 & N170
IMR 7828 & IMR 7828SC
Good ol' H4831 has worked for years, but isn't the velocity champ it once was when compared to more modern powders.
I'm not a fan of H1000 as I don't believe it burns as slow as claimed, and it is subject to lot to lot variations also.

I agree w/ the other guys, not unusual w/ RL22. I have moved over to 7828, it seems more consistant from lot to lot & a bit slower, gaining a bit more vel. Accuracy is very good in my .260ai, .280 & 7mmDakota, even tryining it in my son's 06 w/ good results.

I've got alot of IMR 4831 sittin' around. I have always seen this powder as a good choice for the 30-06 class of cartridges, but nosler lists a max of 73 gr with their 180 gr bullets for a velocity of 3,160fps. Sounds promising. Any users?

I love RL22 I have never had the lot to lot issue because I use the same lot. I tried the powder on several rifles. They loved it so I bought 3 5# containers of the same lot. In about 10 years I'll worry about it.

Ramrod340's solution is good advice with any powder, but especially so with RL-22.

IMR-4831 tends to be just a little on the fast side for the highest velocities with a .300 Winchester, but give it a try. It won't miss the top by more than 50 fps. I run my .300/180 at 3050 fps and am quite satisfied. However, if you don't have a chronograph available you'll have no idea what your load is doing. Backing down to 71 grains with your current batch of RL-22 might be providing you with all the velocity you want -- you'll never know until you chronograph it.

IMR-7828 in the new SSC version would be my choice of powders if starting from scratch. H-1000 seems to be a very erratic powder which I would stay away from. H-4831 is a little slower than the IMR version and should also do fine.

BTW, are any of you guys using the 180 gr partition spitzer rather than the protected point. Just wondering if it were safe to use since nosler recommends against it.

I load both, but the p.p. bullet was designed especially for the short neck on the 300 Winchester case, and it also allows for a bit less powder compression in an already crowded case. Trust me, you'll be happy when your bullet's nose isn't smushed by recoil.

A lot of the RL powders have been changed and are made by a different manufacturer. Most are faster and cleaner. If your manual is a few years old, pitch it and buy a new one.
You should never depend on a manual anyway, only on what your gun is telling you. Just because a book says one thing and your gun another is no reason to push the issue.

Personally.....I am going to submit another scenario. The brass is being oversized in what could easily be a "long chamber". I've seen the exact same phenomenon on a friends 300 wby that I loaded for. Once we got the brass to quit expanding 020"-.030" every time we fired the gun the sticky bolt went away. Primer flatness is never a good source for judging if a load is hot or not.
I'm not saying that the particular powder lot is not hot.....it might be....but I have seen oversized brass with medium loads give the same indications as he got.
I would highly recomend getting a stoney point headspace bushing kit or turning the die upwards till closing the bolt is easy before working up any more loads. I own the stoney point kit and would not load without it.

Hey Kraky, just curious as to how you kept the brass from expanding.

I can't figure that either! Full length sizing every time and shooting hot loads will stretch the brass. Everytime the shoulder is set back, brass flows from just foreward of the web until it cracks. Maybe there is no more brass back there to flow foreward!

Normaly a "long" or "oversize chamber" will make the brass shorter with the first firing. If the brass is sized properly for the chamber, or neck sized only, it will not grow in length much unless the loads are extremely hot. Oversizing will lengthen the brass, then it will have to expand all the way again to fit the chamber. A nasty cycle.

As mentioned above, RL 22 has too many lot variations, so I would not push it to the max.. as suggested, an alternative powder would be a better idea....

Contrary to popular trends, look at data for some of the mid burn rate powders for the 300 Mag.. you may sacrifice a 100 to 200 fps tops in max velocity, but those powders are a lot more stable overall, and frequently a lot more accurate...

H 4831 SC is a pretty stable powder in that burn rate, and temp insensitive.. I am not a big fan always of Hodgdon's Australian powders, but that is one of them that works well.. as does Varget... in the extruded stuff...

Personally I am an IMR guy, and RL 19 and down on the Reloader Line...

H 414 is also a pretty smart performer in the 300 Mags...and pretty darn stable...

My most common load in My 300 Winchester is H 1000/ 83 grains.. with a 220 grain Round Nose or a 220 grain SMP partition...MV is 2950 fps...

That is about 5 grains over max, but the powder is slow enough, I haven't experienced any pressure problems... those bullets at that MV sure hit hard and perform very reliably.. and with that high of a sectional density, they penetrate and open up quite nicely....

good luck,
seafire

were the cases trimmed to length after resizing?

I've found that even factory new brass needs FLS and trim...

I am using new Rem brass, which was full-length sized and trimmed prior to loading.

I do alot of loading for friends (which makes me stupid right off the bat). Anyhow alot of what I load for are belted magnums. Because I have the "stoney point" headspace measuring kit I can quickly see how much the brass is growing from the bottom of the shell to the midpoint of the shoulder. (actually from the belt up but you measure from the bottom to the shoulder) I've seen lots of chambers that let the brass grow about .020" to .030". Now the secret is that when I size it that I push the shoulder back to only about .003" to .005" under "that guns chamber length" to get the very best life out of the brass. If I just size it back by letting the die hit the shellholder we are (as mentioned above) in a cycle that quickly ruins the brass. I have a shim kit I got from sinclair that lets me put shims under my sizing die so that I can make adjustments without having to monkey around with the lock ring.
Because I do alot of reloading for so many guns I really don't think I could load without the measuring kit. I think they are about $30-35.
And...as I stated above.....if you are oversizing your brass and it expands alot during firing I have found that it can cause some slightly sticky extraction feelings even though the load is not quite maxed out. It's just something I found a couple of times and for me the phenominon does exist.

I am in the process of working up some loads using diff powders. I am going to give IMR4350 and 4831 a try. Also found a couple pounds of Accurate 3100. Anyone using this powder with the 180? Can't seem to find data for it.

I would look at your FL sizing you my very well be pushing the shoulder to far back causing a head space problem.

You said you used NEW Rem. brass and you resized it ??? try it without resizing and then invest in a Lee collet die vs FL sizing, once you fireform your cases the Lee collet is the way to go.