7mm IHMSA

[stsbuyer]

I ended up with a standard rifle in 7mm IHMSA. Anyone out there have any rifle data I could use for starting loads. Plan on using 130 gr matchkings for CPT and 175 gr matchkings for rams. It has a 9 twist Shilen 26-1/12" long on a Remington 40x single shot action.

[lone ringer]

Paul, the 7mm IHMSA is a great caliber that I used for many years before I switched to the 6.5's. I would advice for you to look at the 7-08 Rem loading data and reduce the loads by 3 to 4 grains. I did not use either one of the bullets you are planning on using so I can't recommend a specific load. Should work good with 34 to 35 gr of powders like VV N140 or Varget with the 130gr bullets and maybe a grain more for the ram load with the 175gr. If you have trouble with sticky or hard set rams you may want to work up a max load using 4350

[stsbuyer]

Tony,

Thanks, I knew someone would have starting information for me. I bought the gun to help out a friend and planned to resell it. I have decided that I will keep it and load some up to shoot this weekend at Texas State. May not shoot the match with it but plan on getting settings and see how it does.

Thanks again,

[lone ringer]

You are welcome Paul, if you decide to keep it and want to buy 300 Savage brass to turn into 7MM IHMSA let me know because I have lots of it on hand.

[stsbuyer]

Well I get a box of Sierra 7MM 175 gr Matchkings to load for rams in the 7MM IHMSA. Now I notice on the box it says for 8.5" twist or faster. Wondering if they will work in a 9" twist. I know long ago I used 175 gr Sierra SP BT in a 7BR.

[xpilot]

Paul, You might try the Hornady 162 AMAX. Works well on the rams (seems like a tougher bullet than the Sierra),and runs fine in a 9 twist.

[lone ringer]

Well I get a box of Sierra 7MM 175 gr Matchkings to load for rams in the 7MM IHMSA. Now I notice on the box it says for 8.5" twist or faster. Wondering if they will work in a 9" twist. I know long ago I used 175 gr Sierra SP BT in a 7BR.

You should not have trouble with them at 500 meters, at longer distances maybe. I have also used them on a 7mm BR with a 9 twist barrel and they shot fine, the problem with having an 8 twist barrel is that they sometimes do not like lighter bullets. I have a 7mm TCU with an 8 twist barrel that does not like anything lighter than 168's. Load them with 35 to 36 gr of Varget or similar burning rate powder and try them at 500 that is the only way to find out.

[7mm250]

I have been shooting the 7ihmsa in HPfor many years. You donot have to load this round as hot as 3-4 grains less than a 7-08.Ihave used mostly h4895 in both the rifle and pistols. I found that a load of about 33.5 grs and a Hor.139gr btsp works great for c-p-t. for the rams iuse 35.5 grs of h4895 with any 160-168 gr bullet and have found that 175 gr bullets are not needed.
Over the years I have used ww748,accurate arms 2460,and other similar burning rate powders and have found this round very easy to find a load. The general idea of using is to reduce the effects of recoil over a 40-60 rd match.
work with it and you will be very satisified.
Richard Harper N.O.La.

[stsbuyer]

Richard,

I purchased 130 and 175 match kings so I plan on giving them a try. I will give the H4895 a try as it was one of my favorite powders for 7mm-08 and 308.

I am having a new scope mount built, once it is done I will start testing.

Thanks,

[Snake]

Well I get a box of Sierra 7MM 175 gr Matchkings to load for rams in the 7MM IHMSA. Now I notice on the box it says for 8.5" twist or faster. Wondering if they will work in a 9" twist. I know long ago I used 175 gr Sierra SP BT in a 7BR.

I have also used them on a 7mm BR with a 9 twist barrel and they shot fine, the problem with having an 8 twist barrel is that they sometimes do not like lighter bullets.

Light bullets in an 8 twist can be driven slower ...its impossible to over stabilize a bullet. If an 8 twist doesn't like a bullet its probably the bullet/load not the twist 'cause it impossible to overstabilize. a 168 VLD or a 175 is on the ragged edge in a 9 twist unless driven real hard. As you know boattails don't stop yawing until they're past 300 yds. Note that the bench rest boys shoot flat base only out to 300...they do not use boattails. In fact i use 120 ballistic tips in my 8 twist 7-08...it shoots less than .5 minute at 200....of course that's with 37 grs of varget ( alight load). I say that if the 175 works in your 9twist then good for you...don't try 10 twist

[Siluetas55]

Paul,

Realize that this is an older thread but, have you had a chance to load test the 7mm IHMSA? I've been shooting this cal since '88 and have some Jack Hill loads that I can share, if you'd like. Lone Ringer and Jack were the folks that got me interested in this cal for standard rifle.

Sincerely,

Steve Harris
Reno, NV

[stsbuyer]

Steve,

Sorry did notice your post until today. No i have not done any testing yet. The scope base is not ready and we are changing the threads in the action to 8-40 from 6-48. Not sure who did it but the gun had three holes 6-48 and one 8-40. So I decided that it would be better to just change the rest while the base was being built. If you have some load data I would appreciate the information. As you know most of the data in loading manuals is geared toward pistol silhouette. If you like you could just email the data to me.

Thanks,

[email protected]

[edgehit]

I am interested in your load data as well. Can please share in a post? Thanks

[Siluetas55]

Paul and Joe,

Two sets of 7mm IHMSA load data follow. The first set were the loads that I worked up with Jack's assistance back in '88. I initially used reformed .308 brass as I had a ton of it. A pain in the backside. Switched to reforming .300 Savage brass, either Winchester W-W Super or Remington R-P. Much better results. Used a Redding reforming die. The second set of loads were loads that Jack used in his rifles. My barrel length is 25.5" and Jack's were 25 to 26". Both of us utilized a 1-in-9 twist, Donnelly or Shilen barrels.

C/P/T: 150 gr. SGK or SMK, 34.0 gr. IMR4895, Ref. .300 Sav., Fed 210
T/R: 168 gr. SMK, 34.0 gr. IMR4895, Ref. .300 Sav., Fed 210
T/R: 175 gr. SGK, 34.0 gr. IMR4895, Ref. .300 Sav., Fed 210

If you're not an IMR4895 fan, here are some other loads that I tried and liked (match bullets and IMR powders were tough to get at the time):

C/P/T: 150 gr. SGK, 32.0 gr. H-335, Ref. .300 Sav., Fed 210
T/R: 175 gr. SGK, 38.5 gr. H-414 or W760, Ref. .300 Sav., Fed 210

Old school but, definitely accurate in my rig. We shot a lot of hard-set targets and heavy winds at the time so, I stayed with the heavier bullets

Jack Hill 7mm IHMSA loads:

C/P/T: 150 gr. SMK, 36.0 gr. Varget, Ref. .300 Sav., Fed 210
T/R: 168 gr. SMK, 37.0 gr. IMR4064, Ref. .300 Sav., Fed 210
R: 168 gr. Berger VLD, 34.0 gr. IMR4895, Ref. .300 Sav., Fed 210

Hope these loads help you in your efforts.

Sincerely,

[edgehit]

Thank you very much for sharing! I have a lot of H335 and Varget and will likely use those loads as a starting place for 162g A-Max